What is the sum of the integers between -90 and 95, inclusive?

Question

A. 5
B. 185
C. 465
D. 4,275
E. 4,560

zhanbo · Answer

It took me 32 seconds to select (C), i.e 465

-90 -89 -88 .... +88 + 89 + 90 + 91 + 92 + 93 + 94 + 95
= 91 + 92 + 93 + 94 + 95
= 93 X 5

rajatchopra1994 · Answer

Explanation:
Calculate Sum from : -90 to 0 & 1 to 95
From: 1 to 95
Sum= 95*96/2 = 4560
From: -90 to 0
Sum= - (90*91)/2 = -4095

Now From -90 to 95 = 4560-4095
=465

IMO-C

zhanbo · Answer

This is a logical approach with right answer, but we can cancel out -90 with 90, -89 with 89, etc. That way, we only need to worry about the sum from 91 to 95. It is always a good idea to reduce the calculation for higher speed and accuracy.

Abhishek009 · Answer

-90 to 90 , sum = 0

91 - 95 = 91 + 92 + 93 + 94 + 95 => 465 , Answer will be (C)

lavanya.18 · Answer

All numbers between -90 and 90 will get cancelled.

So, we have to add 91+91+93+94+95= 465, which is our answer!!

ManifestDreamMBA · Answer

Estimate since numbers are far apart. values -90 to 90 will all get cancelled out. Then we will have 5 values b/w 90 and 100, so the answer will be between 90*5 = 450 and 100* 5 = 500. Only C works

What is the sum of the integers between -90 and 95, inclusive?

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What is the sum of the integers between -90 and 95, inclusive?

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