The sum of eight consecutive (one after the other) numbers is 88. What are the numbers?

1 Answer
Apr 17, 2016

If we call the first number, an unknown, nn, then the next consecutive numbers are n+1,n+2. . . n+7n+1,n+2...n+7.

Thus, when we add all the terms, from nn to n+7n+7 together, and set that equal to 8888, we get:

8n+28=888n+28=88

Note that 1+2+3+4+5+6+7=281+2+3+4+5+6+7=28.

This gives us

8n=608n=60

n=15/2n=152

Note that this is not an integer, which leads us into shaky territory: its hard to define 15/2,17/2,19/2. . .152,172,192... as "consecutive numbers," per se.

A more apt description of this would be that the sum of these 88 numbers, all of which are 11 away from the next highest number, have a sum of 8888.

15/2+17/2+19/2+21/2+23/2+25/2+27/2+29/2=88152+172+192+212+232+252+272+292=88