Answer :

iGreen
Convert 3/10 to a fraction over 50.

50 / 10 = 5

Multiply both the numerator and denominator by 5:

5 * 3 = 15
5 * 10 = 50

15/50

So 15 fiftieths would equal three tenths.
use ratio and proportion

x/50=3/10
cross multiply
10x=150
     x=15