Herllo, aznmartinjai!

Find the average for the 1000 whole numbers from 1 to 1000, inclusive.

Simple . . . add the numbers from 1 t0 1000 and divide by 1000 . . .LOL!

If you know the formula for the sum of the firstnpositive integers, it's faster.

. . The sum of the firstnpositive integers is: .n(n + 1)/2

So the sum is: .1000(1001)/2

And the average is: .1000(1001)/2 ÷ 1000 .= .500.5

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If you didn't know that formula, you could still find the sum.

We have: .1 + 2 + 3 + . . . + 998 + 999 + 1000

Add pairs of numbers "from the ends".

. . 1 + 1000 .= .1001

. . .2 + 999 .= .1001

. . .3 + 998 .= .1001

. . . . .and so on . . .

How many such pairs are there?

. . There arefive hundredpairs.

Therefore, the sum is: .1001 × 500 .= .500,500