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GRE Statistics (Select One) http://www.800score.com/forum/viewtopic.php?f=12&t=3526 
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Author:  questioner [ Mon Dec 06, 2010 2:00 pm ]  
Post subject:  GRE Statistics (Select One)  
Three students were given three tests, the results of the first two tests are shown above. Student 1 and Student 3 received equal scores on Test 3. As a result, Student 1’s average (arithmetic mean) score over the three tests was 50 percent higher than Student 3’s average. What was the score Students 1 and 3 received on Test 3? A. 33 B. 34 C. 35 D. 36 E. 39 (B) Let x be the score that both Student 1 and Student 3 received on Test 3. Since Student 1's average is 50% higher than Student 3's average, Student 1's average is 1.5 times that of Student 3. The average for Student 1 is (30 + 50 + x)/3, and the average for Student 3 is (14 + 28 + x)/3. So we can solve for x as follows: (30 + 50 + x)/3 = ((14 + 28 + x)/3) × 1.5 (80 + x)/3 = ((42 + x)/3) × 1.5 (80 + x)/3 = (63 + 1.5x)/3 80 + x = 63 + 1.5x 17 = 0.5x x = 34. The correct answer is choice (B).  Can you tell me how you got 1.5 for 50%? I would think 50 percent is .5. Thank you.

Author:  Gennadiy [ Mon Dec 06, 2010 2:13 pm ] 
Post subject:  Re: math (test 2, question 19): algebra 
Quote: .. Student 1’s average (arithmetic mean) score over the three tests was 50 percent higher than Student 3’s average. Student 3’s average is considered to be 100%. If we denote it by y, then it is 100% of y, which is the same as 1 × y. Student 1’s average is 50% higher. Therefore it is (100% + 50%) of y, which is the same as (1 + 0.5) × y = 1.5y. If we were told that Student 1’s average score was 50% of the student 3’s average score, then it would be 50% of y, which would be the same as 0.5y. 
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