Question

In first 400 natural nunbers.Divisible by 2 are removed and then those divisible by 5 are also removed. How many of given nunbers will be left now

Answer 1

200 number in first 400 natural number can be divided by 2 and 80 number in first 400 natural number can be divided by 5
=200+80=280
after subtractinf 280 from 400 we get
120 it is answer