CBSE Class 3 Mathematics Assignment Set 06

ASSIGNMENT NO 2

1. Fill in the blanks:
a. \(1190 + 9780 + 6338 = 9780 + 6338 + 1190\)
b. \(726 + 2334 + 5461 = 5461 + 2334 + 726\)
c. \(3223 + 7890 + 100 = 100 + 7890 + 3223\)

Question 1. Fill in the blanks:
a. \(1190 + 9780 + 6338 = 9780 +\) ............................ \(+ 1190\)
b. \(726 +\) ............................ \(+ 5461 = 5461 + 2334 + 726\)
c. \(3223 + 7890 + 100 =\) ............................ \(+ 7890 + 3223\)
Answer:
a. 6338 (Using the commutative property of addition, the order of addends does not change the sum.)
b. 2334 (Matching the terms on both sides of the equals sign.)
c. 100 (Matching the terms on both sides of the equals sign.)
In simple words: The numbers on both sides of the equals sign must be the same, even if their order is changed.

Exam Tip: Look closely at the numbers given on both sides and fill in the missing number that makes the equation balanced.

Question 2. Fill in the blanks:
a. \(8990 + 1000 =\) ............................
b. \(259 + 10 =\) ............................
c. \(777 + 100 =\) ............................
Answer:
a. 9990
b. 269
c. 877
In simple words: Add 1000, 10, or 100 to the given numbers by increasing the digit in the respective place value.

Exam Tip: When adding powers of 10, only the digit in the place corresponding to the value being added changes (unless there is a carry-over).

Question 3. Guess the addends and fill in the blanks:
a. \(30 +\) ............................ \(= 80\)
b. \(700 +\) ............................ \(= 900\)
c. \(1700 +\) ............................ \(= 1800\)
d. ............................ \(+ 600 = 800\)
Answer:
a. 50 (Since \(80 - 30 = 50\))
b. 200 (Since \(900 - 700 = 200\))
c. 100 (Since \(1800 - 1700 = 100\))
d. 200 (Since \(800 - 600 = 200\))
In simple words: Find the missing part by subtracting the given number from the total sum.

Exam Tip: Use subtraction to find a missing addend in an addition equation.

Question 4. A train is carrying 1200 passengers. 720 more passengers get into it. How many passengers are there in the train now?
Answer:
Number of passengers currently in the train = 1200
Number of new passengers who got in = 720
Total number of passengers in the train now = \(1200 + 720 = 1920\)
In simple words: Add the new passengers to the ones already on the train to get the total count.

Exam Tip: For word problems involving words like "more" or "in all", perform addition.

Question 5. In class III, there are 15 girls and 20 boys. How many students are there in all?
Answer:
Number of girls = 15
Number of boys = 20
Total number of students = \(15 + 20 = 35\)
In simple words: Combine the number of girls and boys to find the total strength of the class.

Exam Tip: Always write proper statement lines before performing the final calculation in word problems.

Question 6. Add the following:
Answer:

In simple words: Add column by column starting from the ones place, carrying over when the sum is 10 or more.

Exam Tip: Align numbers neatly by their place values (ones, tens, hundreds, thousands) before adding to avoid calculation mistakes.