GMAT Problem Solving (PS) | If the average of a sequence of consecutive multiple of 18 is 153, and

answer is 7

my method-
first find the lowest term=270+x/2=153
x=36

now find the number od terms 270 - 36/18 +1=14

as the number os terms is even the median or average will be 7th +8th term /2.this concludes the 7th term is less than 153

so there are total 7 terms less than 153 and 7 terms greater than 153.

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