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mlane25269
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The question asks us the followingmlane25269 wrote:Hi! Can someone explain? Thanks!
[x+(x+1)+(x+2)+.....+(x+10)]/11=?
You can phrase the question as what is the value of x
Statement I
Average of first nine integers is 7
[x+(x+1)+(x+2)+.....+(x+8)]/9= 7
Sufficient.
Statement II
Average of last nine integers is 9
[(x+2)+(x+3).....+(x+10)]/9= 9
Sufficient.
Hence the answer is D.












