Question

What is the least number which when divided by 15, 18 and 36 leaves the same remainder 9 in each case and is divisible by 11?
1. 1080
2. 1071
3. 1269
4. 1089

Answer 1

Correct Answer - Option 4 : 1089

Concept used:

LCM of numbers

Calculation:

Take LCM of 15, 18, 36

2	15,18, 36
3	15,9,18
3	5, 3, 6

    5, 1, 2

⇒ LCM = 2 × 3 × 3 × 5 × 1 × 2 = 180

⇒ LCM = 180

The required number which is exactly divisible by 11

⇒ 180x + 9

Put x = 6

⇒ 180 × 6 + 9

⇒ 1089 is divisible by 11.

∴ The required number is 1089.