Samacheer Kalvi Class 5 Maths Solutions Term 1 Chapter 2 Numbers Exercise 2.4

Question 1. Write the number name
(a) 11000
(b) 34000
(c) 100000
(d) 98,364
(e) 37,689
(f) 46,763
(g) 4,00,000
(h) 12,00,000
Answer:
(a) 11000 - Eleven thousand
(b) 34000 - Thirty four thousand
(c) 100000 - One lakh
(d) 98,364 - Ninety eight thousand three hundred and sixty four
(e) 37,689 - Thirty seven thousand six hundred and eighty nine
(f) 46,763 - Forty six thousand seven hundred and sixty three
(g) 4,00,000 - Four lakhs
(h) 12,00,000 - Twelve lakhs
In simple words: To write a number name, say out the number as you would read it aloud. Remember to use the correct place value terms like thousands, lakhs, and crores.

🎯 Exam Tip: Practice writing number names for numbers with different place values, especially those involving lakhs and crores in the Indian number system. Pay attention to the use of hyphens in compound number names (e.g., twenty-one).

Question 2. Answer the following Represent given values in Abacus.

Question 2.a) 3 tens crores, 7 crores, 6 ten lakhs, 7 lakhs, 4 tens and 7 ones
Answer: The number is 37,67,00,047. Here is how it looks on an abacus:

In simple words: Each rod on the abacus shows a different place value. We count the number of beads on each rod to find the digit for that place. For 37,67,00,047, the abacus shows beads corresponding to each digit in its correct place.

🎯 Exam Tip: Always make sure the number of beads on each rod matches the digit in that place value. It helps to write the number and its place values clearly below the abacus.

Question 2.b) Find the place value of 7 and 4 of this numbers 34578910.
Answer: For the number 3,45,78,910, here is the place value representation on an abacus:

The number is 3,45,78,910.
The place value of 7 is 7 multiplied by 10,000, which is 70,000.
The place value of 4 is 4 multiplied by 10,00,000, which is 40,00,000.
In simple words: The place value tells us how much a digit is worth based on its position in the number. To find the place value, multiply the digit by the value of its position (like tens, thousands, lakhs, etc.).

🎯 Exam Tip: Identify the place of each digit accurately. For larger numbers, it helps to write down the place values (ones, tens, hundreds, thousands, etc.) from right to left above the digits.

Question 2.c) Write in numerals.
a. One crore forty thousands and four.
b. Sixty four lakhs and three.
Answer:
a. One crore forty thousands and four: 1,00,40,004. This number has 1 in the crore place, 40 in the thousands place, and 4 in the ones place.
b. Sixty four lakhs and three: 64,00,003. This number has 64 in the lakhs place and 3 in the ones place, with zeros in between.
In simple words: When writing a number from its name, make sure to put zeros in all the empty place value spots. For example, if "thousands" is mentioned but "hundreds" is not, put zeros in the hundreds, tens, and ones places.

🎯 Exam Tip: Be careful with numbers that skip place values. If a place value is not mentioned (e.g., "hundreds"), you must use a zero as a placeholder in that position.

Question 2.d) Write the number names of the following numbers represented in the Abacus

Figure 1
9,52,86,341
Nine crores Fifty two lakhs eighty six thousand three hundred and forty one.


Figure 2
2,56,79,438
Answer:
For Figure 1, the number shown is 9,52,86,341.
The number name is: Nine crores fifty two lakhs eighty six thousand three hundred and forty one.

For Figure 2, the number shown is 2,56,79,438.
The number name is: Two crores fifty six lakhs seventy nine thousand four hundred and thirty eight.
In simple words: Look at each rod on the abacus and count the beads. Each rod stands for a place value. Combine the numbers from left to right, and then write the full number in words.

🎯 Exam Tip: When converting from an abacus to a number name, make sure to read the place values correctly from left to right (highest to lowest). Double-check the count of beads on each rod for accuracy.

Question 2.e) How many lakhs and hundreds are there in the numbers represented by the Abacus given above.
Answer:
For Figure 1 (9,52,86,341): There are 52 lakhs and 3 hundreds.
For Figure 2 (2,56,79,438): There are 56 lakhs and 4 hundreds.
In simple words: The abacus helps us see how many of each place value there are. For 'lakhs', we look at the digit in the lakhs and ten lakhs place. For 'hundreds', we look at the digit in the hundreds place.

🎯 Exam Tip: Clearly identify the 'lakhs' period (ten lakhs and lakhs) and the 'hundreds' place to accurately state the number of lakhs and hundreds.

Question 2.f) Find the sum of greatest 4-digit number and smallest 5-digit numbers.
Answer:
The greatest 4-digit number is 9,999.
The smallest 5-digit number is 10,000.
To find the sum, we add these two numbers:
Sum \( = 9,999 + 10,000 \)
\( = 19,999 \)
The sum is 19,999. Finding these extreme numbers is key to the calculation.
In simple words: The biggest 4-digit number is 9999. The smallest 5-digit number is 10000. When you add them together, you get 19999.

🎯 Exam Tip: Remember that the greatest number of a given digit count is all nines (e.g., 99 for 2-digits), and the smallest is 1 followed by zeros (e.g., 100 for 3-digits).

Question 2.g) Write the following ascending and descending order.
a. 33,058; 40,978; 97,879; 81,421; 90,470; 47,224
b. 99,999; 11,111; 22,222; 33,333; 44,444; 66,666
Answer:
a. For the numbers 33,058; 40,978; 97,879; 81,421; 90,470; 47,224:
Ascending order (smallest to largest): 33,058; 40,978; 47,224; 81,421; 90,470; 97,879
Descending order (largest to smallest): 97,879; 90,470; 81,421; 47,224; 40,978; 33,058

b. For the numbers 99,999; 11,111; 22,222; 33,333; 44,444; 66,666:
Ascending order (smallest to largest): 11,111; 22,222; 33,333; 44,444; 66,666; 99,999
Descending order (largest to smallest): 99,999; 66,666; 44,444; 33,333; 22,222; 11,111
In simple words: Ascending order means arranging numbers from the smallest to the biggest, like climbing up stairs. Descending order means arranging numbers from the biggest to the smallest, like coming down stairs.

🎯 Exam Tip: To compare numbers, always start by looking at the digit in the highest place value. If they are the same, move to the next digit to the right until you find a difference.

Question 2.h) Write in standard form: 7 lakhs + 5 thousands + 4 tens + 3 ones
Answer:
7 lakhs \( = 7,00,000 \)
5 thousands \( = 5,000 \)
4 tens \( = 40 \)
3 ones \( = 3 \)
Adding these values together gives the standard form:
\( 7,00,000 + 5,000 + 40 + 3 = 7,05,043 \). Always align the place values when adding.
In simple words: To write a number in standard form from its expanded form, you add up all the place values. Make sure to put zeros in any place values that are missing.

🎯 Exam Tip: When writing numbers in standard form from expanded form, use placeholders (zeros) for any missing place values (e.g., if there are no hundreds, write '0' in the hundreds place).

Question 2.i) Add 5 thousands and 3 hundreds to this number 1,34,510
Answer:
The number given is 1,34,510.
We need to add 5 thousands (which is 5,000) and 3 hundreds (which is 300).
So, we need to add \( 5,000 + 300 = 5,300 \) to the number 1,34,510.
\( 1,34,510 + 5,300 = 1,39,810 \). This is a straightforward addition after identifying the values.
In simple words: We take the starting number and add the value of 5 thousands (five thousand) and 3 hundreds (three hundred) to it. The sum is one lakh thirty nine thousand eight hundred and ten.

🎯 Exam Tip: Pay attention to the specific place values mentioned (thousands, hundreds) to ensure you add the correct numerical amounts. Always double-check your addition.

Question 2.j) Subtract smallest 6-digit numbers from greatest 7-digit numbers.
Answer:
The greatest 7-digit number is 99,99,999.
The smallest 6-digit number is 1,00,000.
To find the difference, we subtract the smallest 6-digit number from the greatest 7-digit number:
Subtract \( = 99,99,999 - 1,00,000 \)
\( = 98,99,999 \). The process of identifying the largest and smallest numbers is crucial.
In simple words: The largest number with seven digits is 99,99,999. The smallest number with six digits is 1,00,000. When you take the smaller number away from the bigger one, you get 98,99,999.

🎯 Exam Tip: Clearly define the 'greatest N-digit number' (N nines) and 'smallest N-digit number' (1 followed by N-1 zeros) before performing any calculation.