Question

What is the least five-digit number that is exactly divisible by 21, 35, and 56?

• A. 10000
• B. 10040
• C. 10920
• D. 10080

Answer 1

Answer:

D. 10080

Solution:

Given:

Numbers are 21, 35, 56

Calculation:

LCM of 21, 35, and 56 = 840

So, the 5 digit number must be 840m, where m is a real number.

Now,

For m = 10

Number is 8400

For m = 11

Number is 9240

For m = 12

Number is 10080 which is a 5 digit number

∴ The required number is 10080.