H.C.F and L.C.M Aptitude Test Paper 1

Answer: B

Explanation:

By Division Method

Therefore the HCF is 73

Answer: D

Explanation:

210 = 2 x 5 x 3 x 7 x 1
385 = 5 x 7 x 11 x 1
735 = 5 x 7 x 3 x 7 x 1
HCF = 5 x 7 = 35

Answer: B

Explanation:

Formula:

HCF:

2= 2 x 1
8= 2 x 2 x 2
64= 2 x 2 x 2 x 2 x 2 x 2
10= 2 x 5
HCF =2

LCM:

LCM = 3 x 3 x 3 x 3 = 81

Answer: A

Explanation:

First of all we have to write the numbers as product of the prime factor.
Prime factor of 608 = 2⁵ * 19
i.e.,

And the prime factor of 544 = 2⁵ * 17
i.e.,

So, the HCF of 608 and 544 = common factor in both = 2⁵ = 32
Similarly, The prime factor of 638 = 2 * 11 * 29
The prime factor of 783 = 3* 3 * 3 * 29
So, the HCF of 638 and 783 = 29

Now, the prime factor of 425 = 5 * 5 * 17
The prime factor of 476 = 2*2*7*17
So, the HCF of 425 and 476 = 17

Answer: C

Explanation:
Formula:

LCM:

LCM = 2 x 2 x 5 = 20

HCF:

3=3 x 1
6=3 x 2 x 1
9=3 x 3 x 1
27=3 x 3 x 3 x 1
HCF =3
Formula: