# HCF and LCM Quiz Set 015

### Question 1

Find the least possible number that can be divided by 33, 96 as well as 27?

A

9504.

B

19008.

C

4752.

D

28512.

Soln.
Ans: a

The required number is LCM = 9504.

### Question 2

The product of LCM and HCF of two numbers is 6300? If one of the numbers is 75, what is the other?

A

84.

B

86.

C

85.

D

87.

Soln.
Ans: a

Product of two numbers is equal to the product of their LCM and HCF. So the other number is \$6300/75\$ = 84.

### Question 3

Three lights are flashing at regular intervals. They, respectively, flash after 9, 18 and 27 seconds. How many times do they together flash in 432 seconds?

A

9 times.

B

10 times.

C

8 times.

D

11 times.

Soln.
Ans: a

They will together flash after the LCM of their times. The LCM of 9, 18 and 27 = 54. So they will flash 1 + \$432/54\$ = 9 times.

### Question 4

What is the HCF of 6, 84 and 171?

A

3.

B

6.

C

1.

D

9.

Soln.
Ans: a

The required HCF = 3.

### Question 5

Three lights are flashing at regular intervals. They, respectively, flash after 21, 42 and 63 seconds. How many times do they together flash in 1008 seconds?

A

9 times.

B

10 times.

C

8 times.

D

11 times.

Soln.
Ans: a

They will together flash after the LCM of their times. The LCM of 21, 42 and 63 = 126. So they will flash 1 + \$1008/126\$ = 9 times.