# HCF and LCM Quiz Set 001

### Question 1

What is the HCF of 12, 48 and 171?

A

3.

B

6.

C

1.

D

9.

Soln.
Ans: a

The required HCF = 3.

### Question 2

The product of LCM and HCF of two numbers is 3360? If one of the numbers is 80, what is the other?

A

42.

B

44.

C

43.

D

45.

Soln.
Ans: a

Product of two numbers is equal to the product of their LCM and HCF. So the other number is \$3360/80\$ = 42.

### Question 3

Which is the smallest number which when divided by 15, 12 or 14 leaves 12, 9, 11 as the respective remainders?

A

417.

B

418.

C

416.

D

419.

Soln.
Ans: a

By inspection, the difference between the numbers and their respective remainders is same = 3. The LCM of 15, 12 and 14 = 420. So the required number is 420 - 3 = 417.

### Question 4

Which is the least number which must be added to 23933 so that it becomes divisible by 18, 95 and 84?

A

7.

B

8.

C

6.

D

9.

Soln.
Ans: a

The LCM of 18, 95 and 84 = 23940. The lcm when divided by either of these numbers leaves the remainder 0. The minimum number to be added is 23940 - 23933 = 7.

### Question 5

What is the LCM of \${6/13}\$, \$3{3/5}\$ and \${2/9}\$?

A

18.

B

19.

C

20.

D

21.

Soln.
Ans: a

The LCM of numerators 6, 18 and 2 is 18. The HCF of denominators 13, 5 and 9 is 1. So the required LCM of the given fractions is 18/1 = 18.