On his first 3 tests, Rajeev received an average score of N points. If

Question

On his first 3 tests, Rajeev received an average score of N points. If on his fourth test, he exceeds his previous average score by 20 points, what is his average score for his first 4 tests?

A) N
B) N + 4
C) N + 5
D) N + 10
E) N + 20

Source: Chili Hot GMAT

hopeful101candidate · Answer

Total points from first three tests: 3N
Points on fourth test: N + 20

Total points on all four tests: 3N + (N + 20) = 4N + 20

Average score for first four tests: (4N + 20)/4 = N + 5

Answer is C.

vietnammba · Answer

The answer is C ( n+5)
Sum of score of his first 3 tests: 3n
His 4th test score: n+ 20
Sum of his 4 tests: 4n+20
=> Average: 4n+20/4 = n+5

AliciaSierra · Answer

Average =   \frac{(Sum of Items)}{(Number of Items)}

It is given that average of first three tests is N i.e.  \frac{Sum of First Three Tests}{3}   =   N 
So Sum of First Three Tests = 3N

As per question, on his fourth test, he exceeds his previous average score by 20 points
i.e. he has scored  N+ 20  in fourth test .

So  Average  of 4 tests = \frac{(3N+ N+20)}{4}  = N+5

Answer: C

PareshGmat · Answer

Answer = C) N + 5

Total of 1st 3 tests= 3N

4th test score = N + 20

Total of all 4 tests = 4N + 20

Average = N + 5

rishit1080 · Answer

Use plugging in to answer this question. Say he got a 60 on all of his first 3 tests to give him an average score of 60 points, so N=60. On his fourth test he would have scored 80 points. Using simple math we get the average to be 260/4. Simple calculations prove this to be 65, which is N + 5.

ScottTargetTestPrep · Answer

The sum of the first 3 test scores is 3N, and the 4th test score is N + 20, so the sum of all 4 test scores is:

3N + N + 20 = 4N + 20

So, his average score on the 4 tests is:

(4N + 20)/4 = N + 5

Answer: C

TheNightKing · Answer

N=3

Average = N

New Total = N+20

New N=4

Average = N+5

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On his first 3 tests, Rajeev received an average score of N points. If

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