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\\December 6, 2023 12:53 PM Surender Prajapati Proof 5 Reader _________________________ Date: ___________________74

Practice time 5B

1. Find the first six multiples of:

(a) 5 (b) 7 (c) 11 (d) 13

2. Write the first five even multiples of:
(a) 9 (b) 13 (c) 15 (d) 25

3. Write the following.

(a) The 5th multiple of 8 (b) The 8th multiple of 9

(c) Multiples of 12 less than 144 (d) Multiples of 3 between 20 and 50

(e) Multiples of 9 between 50 and 100

(f) The first multiple of 9 which is exactly divisible by 8.
4. Find the first four common multiples of the following numbers. then circle

the smallest common multiple.

(a) 4 and 5 (b) 3 and 5 (c) 2 and 7 (d) 6 and 8 (e) 10 and 20

test oF DivisiBility

When we divide a number by another number and we get 0 as remainder, then the
number is called divisible by another number.

Let us divide both 85 and 88 by 5. 17 5 88 17
By dividing 85 by 5, we get remainder 0. 5 85 5
5
35
So, 85 is divisible by 5. 35 38
35
By dividing 88 by 5, we get remainder 3 instead of 0. 0 3
So, 88 is not divisible by 5.

There are certain tests or rules using which, we can tell whether a number is divisible
by another number or not without actually performing the division.
divisibility by 2

rule: All even numbers are divisible by 2. This means that numbers ending in 0, 2,
4, 6 and 8 are divisible by 2.

examples: 10, 256, 3498 are divisibile by 2.
divisibility by 3

rule: If the sum of all digits of a number is divisible by 3, then the number itself is
divisible by 3.

example: In 24, 2 + 4 = 6 and 6 ÷ 3 = 2

So, 24 is divisible by 3.

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