In this problem, you add 21 and 29. That results in 50 and you can either:
1. Divide 29 by 50 and multiply 100. 29/50= .58 * 100= 58% or
2. Since percentage is based on 100 and the denominator is 50, multiply the top and bottom by 2 like so.
29 x 2 = 58
--- -- ----- so that makes your percentage 58.
50 x 2 = 100
Hope this is clear enough.
