Question

What are the largest 4 digit and the smalest 3 digit no divisible by 6,15,21,24?

Answer 1

Answer:

Step-by-step explanation:6 = 2 × 3

15 = 5 × 3

21 = 7 × 3

24 = 2 × 2 × 2 × 3

thus lcm = 2 × 2 × 2 × 3 × 5 × 7 = 840.

The largest 4 digit number is = 9999

9999 = (840 × 11) + 759

remainder = 759

the largest number divisible by 6, 15, 21 and 24 is

= 9999 - 759

= 9240

The smallest 3 digit number  divisible by 6, 15, 21 and 24 is

Lcm of 6, 15, 21 and 24

= 840