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Mathematics>Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

The odometer of a new automobile functions improperly and registers only 2 miles for every 3 miles driven. If the odometer indicates 48 miles, how many miles has the automobile actually been driven?

(A) 144
(B) 72
(C) 64
(D) 32
(E) 24

答案和解析

答案：B

解析：

In this problem, you are told that the odometer registers only 2 miles for every 3 miles driven. So the ratio of miles registered to miles driven is 2 to 3 or 2/3. This can be expressed as

odometer reading/actual miles = 2/3

If the odometer indicates 48 miles, the actual miles can be found using using the above relationship as follows:

48/x = 2/3 and 2x = 144 and x=72

So if the odometer indicates 48 miles, the actual number of miles driven is 72.