Mitch is saving money to go on a camping trip this summer. So far he has saved $160 which is 40% of the money needed to go on the camping trip. Which equation below would one write to figure out the total amount of money Mitch needs to save to go on the camping trip?

A. 160/x = 40/100
B. 160/100 = 40/x
C. 40/100 = x/160
D. 40/160 = x/100