An airplane displays trip information to passengers...

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An airplane displays trip information to passengers in two ways: how much time is left in the flight, and what percent of the trip duration has been completed. When Curtis first checks the display, the clock reads 5:50, meaning that there are 5 hours and 50 minutes left for the trip, and the display shows that 12.5% of the trip has been completed. What will the clock show when the trip is 50% complete?

A. 2:00
B. 2:25
C. 2:45
D. 3:10
E. 3:20

The OA is E.

I don't understand this PS question. Please, can any expert explain it for me? Thanks.

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by ErikaPrepScholar » Wed Nov 01, 2017 8:57 am
If 12.5% of the trip has been completed when there are 5 hours and 50 minutes left in the flight, this means that 5 hours and 50 minutes = 87.5% of the trip. Converting this into minutes, we know that 87.5% of the trip is equal to 350 minutes.

We want to know what the clock will read when the trip is 50% complete. This means that the clock will read the amount of time left in the trip, which is also 50%. In other words, we want to find how much time 50% of the trip is equal to.

Let's set up a cross-multiplication equation using what we know.

$$\frac{350\ \min}{87.5\%}=\frac{x}{50\%}$$

87.5x = 17500

x = 200 min

Converting back into hours and minutes gives us 3 hours and 20 minutes, or 3:20, which is answer choice E.
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