Bunuel wrote:

The average of 5 consecutive integers starting with m as the first integer is n. What is the average of 9 consecutive integers that start with (m + 2)?

A. m + 4

B. n + 6

C. n + 3

D. m + 5

E. n + 4

If the first of the five consecutive integers is m, then the four remaining integers are m + 1, m + 2, m + 3, and m + 4. Since the average of any number of consecutive integers is also the median, the average is m + 2. So, n = m + 2.

Likewise, if the first of the nine consecutive integers is m + 2, then the eight remaining integers are m + 3, m + 4, m + 5, m + 6, m + 7, m + 8, m + 9, and m + 10. Again, since the average of any number of consecutive integers is the median, the average is m + 6. Since m + 2 = n, m + 6 = n + 4. So, n + 4 is the average of the nine consecutive integers.

Answer: E.

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Jeffery Miller

Head of GMAT Instruction

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