Find the number ABCD such that when multipled by 4 gives DCBA.

We need to find a number ABCD such that,  4(ABCD) = DCBA
These problems can be tricky and/or tedious, but this one isn't too bad.

Find the kth number with prime factors 3, 5 and 7

Find the kth number with prime factors 3, 5 and 7

Design an algorithm such that we have to find the k th element in the array such that their only prime factors are 3,5 an 7.
Example: Array will contain 1,3,5,7,9,15,21,25,...
We have to return the kth element in array

percentage and profit

Percentage

Percent literally means per cent, cent as in century. Thus, percent means per 100' and is represented with the symbol %

This means that any data, a out of b, is proportionally reduced or increased so as to be ' out of 100'

Example