HG10 wrote:In an increasing sequence of 10 consecutive integers, the sum of the first 5 integers is 560. What is the sum of the last 5 integers in the sequence?
A. 585
B. 580
C. 575
D. 570
E. 565
#85, OG 12
With evenly spaced integers:
Average = median = sum/number.
Sum = number*median.
In the problem at hand:
The median of the first five integers = sum/number = 560/5 = 112.
Each integer in the second set of five integers is 5 greater than the corresponding integer in first set of five integers.
Thus, the median of the last five integers = 112+5 = 117.
Thus, the sum of the last five integers = number*median = 5*117 = 585.
The correct answer is
A.
Last edited by
GMATGuruNY on Wed Apr 11, 2012 5:18 pm, edited 1 time in total.
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