Question

How do you solve `2/5 + 7/8 = y/20`?

Answer 1

Multiply through by `20` to find:

`y = 20*y/20 = 20*(2/5+7/8)`

`=(20*2/5)+(20*7/8)`

`= (cancel(5)*4*2)/cancel(5) +(cancel(4)*5*7)/(cancel(4)*2)`

`= 8 + 35/2`

`=16/2+35/2`

`=51/2`