The Official SAT Question of the Day™

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


If United States imports increased 20 percent and exports decreased 10 percent during a certain year, the ratio of imports to exports at the end of the year was how many times the ratio at the beginning of the year?


A 12/11
B 4/3
C 11/8
D 3/2
E 2

Correct Answer: B

Here's Why:

Express What You Know in Mathematical Terms

Write the ratio of imports to exports as .

At the end of the year, imports were up by 20%. So the end-of-year imports can be expressed as 100% of the start-of-year imports plus 20%, or 120% of I.

At the end of the year, exports were down by 10%. So the end-of-year exports can be expressed as 100% of the start-of-year exports minus 10%, or 90% of E.

The ratio of imports to exports at the end of the year can be expressed as 120I/90E.

This is equivalent to 4/3 of I/E.


Difficulty: Hard
Question Type: Standard Multiple Choice

(Mathematics)