Question

Kenji has 2500 Japanese yen. If 1 U.S. dollar equals 90.39 Japanese yen, about how many dollars can Kenji buy for his yen?

Answer 1

90.39/1=2500/x
90.39x=2500
x≈27.66

Kenji could buy about $27.66 

Answer 2

1 USD = 90.39 Yen.
2500 Yen * 1 USD / 90.39 Yen = 27.66 USD. Tip: the Yen cancels out.