Question

how many numbers from 1 to 400 divisible by both 3 and 5 but not by 30​

Answer 1

Answer:

This means we have to count all the numbers which are either divisible by 3 or by 5 or by both. hence 133 numbers are divisible by 3 between 1 and 400. 5, 10, 15, ………., 395 are the numbers which are divisible by 5. hence 79 number are divisible by 5 between 1 and 400.

Answer 2

Answer:

13

Step-by-step explanation:

Numbers divisible by 3&5 between 1-400 are 400/15 = 26 (15 is lcm)

By 30 are 400÷30=13

(all numbers which are divisible by 30 are obviously divisible by 15)

So ans is 26-13=13