Tim C. answered 04/30/17
Tutor
5.0
(306)
Experienced and Effective Specialist in Praxis Math and GED Math
2/5 x 20 = 8
3/10 x 20 = 6
Therefore, used 8 + 6 = 14.
Therefore, 20 - 14 = 6 left
Therefore, need 14 - 6 = 8