Question

2/5 of a stick is painted red,1/3 of it is painted white. The remaining part is painted blue. What part of the stick is painted blue?

Answer 1

blue part = 1-(2/5+1/3)                                                                                                          = 1-(11/15)                                                                                                             =  4/15

Answer 2

Two by five is painted red
It means six by fifteen is painted red

One by three is painted white
It means five by fifteen is painted white

Then by adding both eleven by fifteen is painted by red nd white

As a result four by fifteen is painted blue