Question

find the least number from which if 15 subtracted the result is exactly divisible by 18,21,28 and 30

Answer 1

First find the LCF of 18,21,28 and 30

WHich is 1260

Then add 15 to this number, which is 1275..

So your answer is 1275 because if 15 is subtracted from this the result is exactly divisible by 18,21.28 and 30.