Page 191 - New Medley 4 Semester 1

In other words, we can say if in two given numbers, bigger number is a
multiple of smaller one, then the bigger is their LCM and the smaller is

their HCF.
Mental Test

Find the LCM and HCF of each of the following mentally.

1. 8, 16 2. 15, 45 3. 36, 18 4. 66, 44

EXERCISE 5.3

A. Find the HCF of the following.
1. 12, 16 2. 10, 30 3. 36, 42 4. 24, 56

5. 4, 6, 8 6. 12, 16, 20 7. 15, 40, 60 8. 20, 40, 60

B. Find the LCM of the following.

1. 2, 3 2. 4, 6 3. 5, 10 4. 8, 10

5. 12, 16 6. 3, 6, 9 7. 4, 6, 10 8. 12, 15, 30

C. 1. Can 18 and 72 be the HCF and LCM of two numbers?

2. Can 6 and 15 be the HCF and LCM of two numbers?

3. Is 12 the HCF of 48 and 84?

4. Is 25 the LCM of 5 and 20?

5. Find the LCM and HCF of 4, 6 and 10. Check whether the HCF is a
factor of the LCM.

Even and Odd Numbers

Even Numbers

The numbers which can be put in pairs are called even numbers or the

multiples of 2 are called even numbers, for example, 2, 4, 6, 8, 10,... are
even numbers.
Odd Numbers

The numbers which cannot be put in pairs are called odd numbers. Any
odd number divided by 2 leaves 1 as the remainder, for example, 1, 3, 5,
7, 9,... are odd numbers.

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