Three people took GMAT practice tests in which the minimum and maximum possible scores are 200 and 800, respectively. They each took a test 4 times, and no one scored below 610 or over 780. If the individual ranges of the three people's scores in those 4 practice tests were 50, 80 and 90, what is the difference between the maximum and minimum possible ranges of all their scores put together.\nOptions:\n(A) 70\n(B) 80\n(C) 90\n(D) 100\n(E) 110
Let’s work this out in a step by step way to be sure we have the right answer.
(B)
According to the information in the question the maximum range would be between 610 and 780(170).

The minimum range would be the greatest range for any one individual, which is listed in the problem as 90.

So the difference between these would be 170-90 or 80.

.

Therefore, the answer is (B)