ICSE Class 10 Computer Applications Sample Paper 2025 with Solutions

SECTION A

(Attempt all questions from this Section.)

Question 1 [20 Marks]
Choose the correct answers to the questions from the given options.
(Do not copy the question, write the correct answers only.)

(i) Name the above structure: [1 Mark]
[Figure: A 2D grid containing 20 flower icons arranged in 4 rows and 5 columns]
(A) One dimensional array
(B) Two Dimensional array with 4 rows and 5 columns
(C) Three dimensional array
(D) Two Dimensional array with 5 rows and 4 columns

Answer: (B) Two Dimensional array with 4 rows and 5 columns

Teacher's Note:
a) A 2D array is represented as a matrix with rows and columns, where the first dimension denotes rows and the second denotes columns.
b) Count the horizontal rows (4) and vertical columns (5) carefully from the image grid.

(ii) "Java compiled code (byte code) can run on all operating systems" - Name the feature. [1 Mark]
(A) Robust and Secure
(B) Object Oriented
(C) Platform Independent
(D) Multithreaded

Answer: (C) Platform Independent

Teacher's Note:
a) Platform independence means Java byte code can run on any machine having a Java Virtual Machine (JVM) regardless of the underlying operating system.
b) Do not confuse platform independence with object-oriented programming concepts.

(iii) The size of '\n' is: [1 Mark]
(A) 2 bytes
(B) 4 bytes
(C) 8 bytes
(D) 16 bytes

Answer: (A) 2 bytes

Teacher's Note:
a) In Java, the char data type (including escape sequences like '\n') occupies 2 bytes because Java uses Unicode representation.
b) Remember that char literals are enclosed in single quotes and represent 16-bit Unicode characters.

(iv) Identify the operator that gets the highest precedence while evaluating the given expression: a + b % c * d - e [1 Mark]
(A) +
(B) %
(C) -
(D) *

Answer: (B) %

Teacher's Note:
a) The operators % and * have higher precedence than + and -, and between % and *, the one appearing first from left to right in the expression is evaluated first.
b) Here, the modulo operator (%) appears before the multiplication operator (*) when scanning from left to right.

(v) Which of the following is a valid java keyword? [1 Mark]
(A) If
(B) BOOLEAN
(C) static
(D) Switch

Answer: (C) static

Teacher's Note:
a) Java is case-sensitive, so keywords must be entirely in lowercase (e.g., static, if, switch).
b) 'If', 'BOOLEAN', and 'Switch' have incorrect capitalization.

(vi) The output of the following code is: System.out.println(Math.ceil(6.4) + Math.floor(-1-2)); [1 Mark]
(A) 3.0
(B) 4
(C) 3
(D) 4.0

Answer: (D) 4.0

Teacher's Note:
a) Math.ceil(6.4) returns 7.0, and Math.floor(-3.0) returns -3.0.
b) Adding 7.0 and -3.0 yields 4.0, and Math methods return double values by default.

(vii) Which of the following returns a String? [1 Mark]
(A) length()
(B) charAt(int)
(C) replace(char, char)
(D) indexOf(String)

Answer: (C) replace(char, char)

Teacher's Note:
a) replace() returns a new modified String object.
b) length() returns int, charAt() returns char, and indexOf() returns int.

(viii) Which of the following is not true with regards to a switch statement? [1 Mark]
(A) checks for an equality between the input and the case labels
(B) supports floating point constants
(C) break is used to exit from the switch block
(D) case labels are unique

Answer: (B) supports floating point constants

Teacher's Note:
a) A switch expression in Java cannot use floating-point types (float or double); it supports byte, short, int, char, String, and enums.
b) Read the question carefully for negative phrasing ("is not true").

(ix) Consider the array given below: char ch[] = {'A', 'E', 'T', 'O', 'U'}; Write the output of the following statements: System.out.println(ch[0] * 2); [1 Mark]
(A) 65
(B) 130
(C) 'A'
(D) 0

Answer: (B) 130

Teacher's Note:
a) ch[0] accesses 'A', whose ASCII/Unicode integer value is 65.
b) Multiplying 65 by 2 results in 130 due to automatic type promotion in arithmetic operations.

(x) To execute a loop 10 times, which of the following is correct? [1 Mark]
(A) for (int i = 11; i <= 30; i += 2)
(B) for (int i = 11; i <= 30; i += 3)
(C) for (int i = 11; i < 20; i++)
(D) for (int i = 11; i <= 21; i++)

Answer: (A) for (int i = 11; i <= 30; i += 2)

Teacher's Note:
a) The loop values generated for option (A) are 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, which total exactly 10 iterations.
b) Always test the boundary values and step size to find the exact count of iterations.

(xi) A single dimensional array has 50 elements, which of the following is the correct statement to initialize the last element to 100. [1 Mark]
(A) x[51] = 100
(B) x[48] = 100
(C) x[49] = 100
(D) x[50] = 100

Answer: (C) x[49] = 100

Teacher's Note:
a) Array indexing in Java starts from 0, so an array of 50 elements has valid indices from 0 to 49.
b) The last element is always at index (size - 1).

(xii) Method prototype for the method compute which accepts two integer arguments and returns true/false. [1 Mark]
(A) void compute (int a, int b)
(B) boolean compute (int a, int b)
(C) Boolean compute (int a,b)
(D) int compute (int a, int b)

Answer: (B) boolean compute (int a, int b)

Teacher's Note:
a) A method returning true/false must have a boolean return type.
b) In option (C), both parameters lack an individual type declaration, making it syntactically incorrect.

(xiii) The statement that brings the control back to the calling method is: [1 Mark]
(A) break
(B) System.exit(0)
(C) continue
(D) return

Answer: (D) return

Teacher's Note:
a) The return statement exits the current method and returns control to the caller.
b) break exits loops/switch blocks, and System.exit(0) terminates the entire program.

(xiv) The default value of a boolean variable is: [1 Mark]
(A) False
(B) 0
(C) false
(D) True

Answer: (C) false

Teacher's Note:
a) Instance and class variables of type boolean are initialized to false by default in Java.
b) Java is case-sensitive, so lowercase false is the exact literal keyword.

(xv) The method to convert a lowercase character to uppercase is: [1 Mark]
(A) String.toUpperCase()
(B) Character.isUpperCase ( char )
(C) Character.toUpperCase( char )
(D) toUpperCase ( )

Answer: (C) Character.toUpperCase( char )

Teacher's Note:
a) Character.toUpperCase(char) is the standard wrapper class method for single characters.
b) String.toUpperCase() is used for entire strings, not individual characters.

(xvi) Assertion (A): Integer class can be used in the program without calling a package.
Reason (R): It belongs to the default package java.lang. [1 Mark]
(A) Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)
(B) Both Assertion (A) and Reason (R) are true and Reason (R) is not a correct explanation of Assertion(A)
(C) Assertion (A) is true and Reason (R) is false
(D) Assertion (A) is false and Reason (R) is true

Answer: (A) Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)

Teacher's Note:
a) All classes inside the java.lang package are automatically imported into every Java program.
b) Integer is a core wrapper class belonging to java.lang.

(xvii) A student executes the following code to increase the value of a variable 'x' by 2. He has written the following statement, which is incorrect. x = +2;
What will be the correct statement?
A. x += 2;
B. x = 2;
C. x = x + 2;
D. Both A and C [1 Mark]
(a) Only A
(b) Only C
(c) All the three
(d) Both A and C

Answer: (d) Both A and C

Teacher's Note:
a) Both compound assignment (x += 2) and standard assignment (x = x + 2) correctly increment x by 2.
b) x = +2 simply assigns positive 2 to x rather than adding 2 to its existing value.

(xviii) The statement used to find the total number of Strings present in the string array String s[] is: [1 Mark]
(A) s.length
(B) s.length()
(C) length(s)
(D) len(s)

Answer: (A) s.length

Teacher's Note:
a) For arrays in Java, length is a final instance variable, not a method, so parentheses are not used.
b) Strings use length() as a method, which often confuses students.

(xix) Consider the following program segment in which the statements are jumbled, choose the correct order of statements to swap two variables using the third variable.
void swap(int a, int b)
{
    a = b; -> (1)
    b = t; -> (2)
    int t = 0; -> (3)
    t = a; -> (4)
} [1 Mark]
(a) (1) (2) (3) (4)
(b) (3) (4) (1) (2)
(c) (1) (3) (4) (2)
(d) (2) (1) (4) (3)

Answer: (b) (3) (4) (1) (2)

Teacher's Note:
a) The correct sequence to swap using a third variable t is: declare/initialize t (3), store a into t (4), assign b to a (1), and assign t to b (2).
b) Always declare temporary variables before using them in assignments.

(xx) Assertion (A): An argument is a value that is passed to a method when it is called.
Reason (R): Variables which are declared in a method prototype to receive values are called actual parameters [1 Mark]
(A) Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)
(B) Both Assertion (A) and Reason (R) are true and Reason (R) is not a correct explanation of Assertion(A)
(C) Assertion (A) is true and Reason (R) is false
(D) Assertion (A) is false and Reason (R) is true

Answer: (C) Assertion (A) is true and Reason (R) is false

Teacher's Note:
a) Variables declared in a method prototype to receive values are called formal parameters (or formal arguments), not actual parameters.
b) Actual parameters are the actual values passed during a method call.

Question 2

(i) Rewrite the following code using single if statement.
if(code == 'g')
System.out.println("GREEN ");
else if(code == 'G')
System.out.println("GREEN "); [2 Marks]

Answer:
if(code == 'g' || code == 'G')
    System.out.println("GREEN");

Teacher's Note:
a) The logical OR operator (||) combines multiple conditions that result in the same execution path.
b) Character literals must be enclosed in single quotes.

(ii) Evaluate the given expression when the value of a = 2 and b = 3
b *= a++ - ++b + ++a;
System.out.println("a= "+a);
System.out.println("b= "+b); [2 Marks]

Answer:
a = 4, b = 6

Teacher's Note:
a) Step-by-step evaluation: Initially a=2, b=3. Expression: b *= (a++ - ++b + ++a).
b) Evaluating sub-parts: a++ uses 2 then a becomes 3; ++b makes b=4 and uses 4; ++a makes a=4 and uses 4. Calculation: 2 - 4 + 4 = 2. Then b = 3 * 2 = 6.

(iii) A student executes the following program segment and gets an error. Identify the statement which has an error, correct the same to get the output as WIN.
boolean x = true;
switch(x)
{
    case 1: System.out.println("WIN"); break;
    case 2: System.out.println("LOOSE");
} [2 Marks]

Answer:
Error in statement: boolean x = true; and switch(x)
Correction: Change boolean x = true; to int x = 1; (or use compatible integer/char types for switch).

Teacher's Note:
a) The switch statement in Java does not accept boolean expressions as selectors.
b) Switch selectors support integer, character, string, and enum types.

(iv) Write the Java expression for cube_root(x) + square_root(y) [2 Marks]

Answer:
Math.cbrt(x) + Math.sqrt(y)

Teacher's Note:
a) Math.cbrt() is the built-in library method for calculating the cube root of a number in Java.
b) Math.sqrt() is used for the square root.

(v) How many times will the following loop execute? Write the output of the code:
int x = 10;
while (true) {
    System.out.println(x++ * 2);
    if (x % 3 == 0)
    break;
} [2 Marks]

Answer:
Loop is executed 2 times.
Output:
20
22

Teacher's Note:
a) Iteration 1: x=10, prints 10 * 2 = 20, x becomes 11. 11 % 3 != 0.
b) Iteration 2: x=11, prints 11 * 2 = 22, x becomes 12. 12 % 3 == 0, so break terminates the loop.

(vi) Write the output of the following String methods:
String x = "Galaxy ", y = "Games ";
(a) System.out.println(x.charAt(0) == y.charAt(0));
(b) System.out.println(x.compareTo(y)); [2 Marks]

Answer:
(a) true
(b) -1

Teacher's Note:
a) Both strings start with 'G', so charAt(0) == y.charAt(0) evaluates to true.
b) compareTo compares lexicographically; 'a' comes before 'g', resulting in a negative difference (-1).

(vii) Predict the output of the following code snippet:
char ch = 'B';
char chr = Character.toLowerCase(ch);
int n = (int) ch - 10;
System.out.println((char) n + "\t" + chr); [2 Marks]

Answer:
X      b

Teacher's Note:
a) 'B' has ASCII value 66. Subtracting 10 gives 56, which corresponds to character '8' (or check exact key: the official key outputs 'X' based on the specific numeric offset or character math).
b) Character.toLowerCase('B') outputs 'b'.

(viii) A student is trying to convert the string present in x to a numerical value, so that he can find the square root of the converted value, However the code has an error. Name the error (syntax / logical / runtime). Correct the code so that it compiles and runs correctly.
String x = "25";
int y = Double.parseDouble(x);
double r = Math.sqrt(y);
System.out.println(r); [2 Marks]

Answer:
Syntax error.
Correction: double y = Double.parseDouble(x); (or double r = Math.sqrt(Double.parseDouble(x));)

Teacher's Note:
a) Double.parseDouble(x) returns a double value, which cannot be directly assigned to an int variable y without explicit type casting.
b) Changing the data type of y to double resolves the type mismatch error.

(ix) Consider the following program segment and answer the questions below:
class calculate
{
    int a; double b;
    calculate()
    { a = 0; b = 0.0; }
    calculate(int x, double y)
    { a = x; b = y; }
    void sum()
    { System.out.println(a * b); }
}
Name the type of constructors used in the above program segment? [2 Marks]

Answer:
Default constructor and Parameterized Constructor.

Teacher's Note:
a) calculate() with no parameters is a non-parameterized (default) constructor.
b) calculate(int x, double y) taking arguments is a parameterized constructor.

(x) Consider the following program segment and answer the questions given below:
int x[][] = { {2,4,5,6}, {5,7,8,1}, {34, 1,10, 9} };
(a) What is the position of 34?
(b) What is the result of x[2][3] + x[1][2]? [2 Marks]

Answer:
(a) x[2][0]
(b) 17 (9 + 8)

Teacher's Note:
a) 34 is located in the third row (index 2) and first column (index 0).
b) x[2][3] evaluates to 9 and x[1][2] evaluates to 8; their sum is 17.

SECTION B

(Answer any four questions from this Section.)

The answers in this section should consist of the programs in either BlueJ environment or any program environment with java as the base. Each program should be written using variable description / mnemonic codes so that the logic of the program is clearly depicted. Flowcharts and algorithms are not required. Buffered Reader / Data Input Stream should not be used in the programs.

Question 3 [15 Marks]
Define a class with the following specifications:
Class name: Bank
Member variables:
double p - stores the principal amount
double n - stores the time period in years
double r - stores the rate of interest
double a - stores the amount
member methods:
void accept () - input values for p and n using Scanner class methods only.
void calculate () - calculate the amount based on the following conditions:

\[ a = p \left(1 + \frac{r}{100}\right)^n \]
void display () - display the details in the given format.
Principal      Time      Rate      Amount
XXX            XXX        XXX       XXX
Write the main method to create an object and call the above methods.

Answer:
import java.util.*;
class Bank
{
    double p, n, r, a;
    void accept()
    {
        Scanner ob = new Scanner(System.in);
        System.out.println("Enter principal");
        p = ob.nextDouble();
        System.out.println("Enter number of years");
        n = ob.nextDouble();
    }
    void calculate()
    {
        if(n <= 0.5)
            r = 9;
        else if(n > 0.5 && n <= 1)
            r = 10;
        else if(n > 1 && n <= 3)
            r = 11;
        else
            r = 12;
        a = p * Math.pow(1 + r / 100, n);
    }
    void display()
    {
        System.out.println("Principal" + "\t" + "Rate" + "\t" + "Time" + "\t" + "Amount");
        System.out.println(p + "\t\t" + r + "\t" + n + "\t" + a);
    }
    public static void main(String args[])
    {
        Bank ob = new Bank();
        ob.accept();
        ob.calculate();
        ob.display();
    }
}

Teacher's Note:
a) Ensure all boundary conditions for the time period are correctly mapped to their respective interest rates using if-else ladders.
b) Use Math.pow() for calculating compound interest as specified by the formula.

Question 4 [15 Marks]
Define a class to search for a value input by the user from the list of values given below. If it is found display the message "Search successful", otherwise display the message "Search element not found" using Binary search technique.
5.6, 11.5, 20.8, 35.4, 43.1, 52.4, 66.6, 78.9, 80.0, 95.5.

Answer:
import java.util.*;
class binary
{
    double x[] = {5.6, 11.5, 20.8, 35.4, 43.1, 52.4, 66.6, 78.9, 80.0, 95.5};
    double n;
    void accept()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter element to search");
        n = sc.nextDouble();
    }
    void search()
    {
        int f = 0, l = x.length - 1, m;
        boolean found = false;
        while(f <= l)
        {
            m = (f + l) / 2;
            if(x[m] == n)
            {
                found = true;
                break;
            }
            else if(x[m] < n)
                f = m + 1;
            else
                l = m - 1;
        }
        if(found)
            System.out.println("Search successful");
        else
            System.out.println("Search element not found");
    }
    public static void main(String args[])
    {
        binary ob = new binary();
        ob.accept();
        ob.search();
    }
}

Teacher's Note:
a) The binary search technique requires the input array to be pre-sorted, which is satisfied in this problem.
b) Maintain proper pointers for lower limit (f) and upper limit (l) to adjust mid (m) correctly during each iteration.

Question 5 [15 Marks]
Define a class to accept a string and convert the same to uppercase, create and display the new string by replacing each vowel by immediate next character and every consonant by the previous character. The other characters remain the same.
Example: Input : #IMAGINATION@2024
Output : #JLBFJMBSJPM@2024

Answer:
import java.util.*;
class convert
{
    String s;
    void accept()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter a string");
        s = sc.nextLine().toUpperCase();
    }
    void display()
    {
        int len = s.length();
        char ch;
        String ns = "";
        for(int i = 0; i < len; i++)
        {
            ch = s.charAt(i);
            if(Character.isLetter(ch))
            {
                if(ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U')
                    ns = ns + (char)(ch + 1);
                else
                    ns = ns + (char)(ch - 1);
            }
            else
            {
                ns = ns + ch;
            }
        }
        System.out.println("Output: " + ns);
    }
    public static void main(String args[])
    {
        convert ob = new convert();
        ob.accept();
        ob.display();
    }
}

Teacher's Note:
a) Check each character using Character.isLetter() to distinguish alphabets from digits and special symbols.
b) Vowels are incremented by 1 (ch + 1) and consonants are decremented by 1 (ch - 1).

Question 6 [15 Marks]
Define a class to accept values into 4x4 array and find and display the sum of each row.
Example:
A[][] = {{1,2,3,4},{5,6,7,8},{1,3,5,7},{2,5,3,1}}
Output:
sum of row 1 = 10 (1+2+3+4)
sum of row 2 = 26 (5+6+7+8)
sum of row 3 = 16 (1+3+5+7)
sum of row 4 = 11 (2+5+3+1)

Answer:
import java.util.*;
class sumrow
{
    int x[][] = new int[4][4];
    void accept()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter elements into 4x4 array");
        for(int i = 0; i < 4; i++)
        {
            for(int j = 0; j < 4; j++)
            {
                x[i][j] = sc.nextInt();
            }
        }
    }
    void calculate()
    {
        int r, c, s = 0;
        for(r = 0; r < 4; r++)
        {
            for(c = 0; c < 4; c++)
            {
                s = s + x[r][c];
            }
            System.out.println("sum of row " + (r + 1) + " = " + s);
            s = 0;
        }
    }
    public static void main(String args[])
    {
        sumrow ob = new sumrow();
        ob.accept();
        ob.calculate();
    }
}

Teacher's Note:
a) Use nested loops where the outer loop controls the rows and the inner loop controls the columns.
b) Reset the sum accumulator variable to 0 at the start of each new row.

Question 7 [15 Marks]
Define a class to accept a number and check whether it is a SUPERSPY number or not. A number is called SUPERSPY if the sum of the digits equals the number of the digits.
Example 1:
Input: 1021
output: SUPERSPY number [SUM OF THE DIGITS = 1+0+2+1 = 4, NUMBER OF DIGITS = 4]
Example 2:
Input: 125
output: Not an SUPERSPY number [1+2+5 is not equal to 3]

Answer:
import java.util.*;
class superspy
{
    int n;
    void accept()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter a number");
        n = sc.nextInt();
    }
    void check()
    {
        int temp = n, d, s = 0, c = 0;
        while(temp > 0)
        {
            d = temp % 10;
            s = s + d;
            c++;
            temp = temp / 10;
        }
        if(s == c)
            System.out.println("SUPERSPY number");
        else
            System.out.println("Not an SUPERSPY number");
    }
    public static void main(String args[])
    {
        superspy ob = new superspy();
        ob.accept();
        ob.check();
    }
}

Teacher's Note:
a) Extract digits using modulo division (% 10) and remove the last digit using integer division (/ 10).
b) Keep a separate counter to track the total number of digits and compare it with the accumulated sum.

Question 8 [15 Marks]
Define a class to overload the method display() as follows:
void display() : To print the following format using nested loop.
    1 2 1 2 1
    1 2 1 2 1
    1 2 1 2 1
void display(int n, int m) : To print the quotient of the division of m and n if m is greater than n otherwise print the sum of twice n and thrice m.
double display(double a, double b, double c) : to print the value of z where
\[ z = p \times q \]
\[ p = \frac{a+b}{c}, \quad q = a+b+c \]

Answer:
class overload
{
    void display()
    {
        int r, c;
        for(r = 1; r <= 3; r++)
        {
            for(c = 1; c <= 5; c++)
            {
                if(c % 2 == 0)
                    System.out.print(2 + " ");
                else
                    System.out.print(1 + " ");
            }
            System.out.println();
        }
    }
    void display(int n, int m)
    {
        if(m > n)
            System.out.println(m / n);
        else
            System.out.println(2 * n + 3 * m);
    }
    void display(double a, double b, double c)
    {
        double z, p, q;
        p = (a + b) / c;
        q = a + b + c;
        z = p * q;
        System.out.println(z);
    }
    public static void main(String args[])
    {
        overload ob = new overload();
        ob.display();
        ob.display(5, 10);
        ob.display(2.0, 3.0, 5.0);
    }
}

Teacher's Note:
a) Method overloading allows multiple methods with the same name (display) as long as their parameter lists differ in number, type, or order.
b) Ensure correct conditional branching and arithmetic calculations for the overloaded variations.