Question

what is the average of first 100 positive numbers??

Answer 1

First 100 postive numbers are:

1, 2, 3,4,5, ......................... 100.

These number are in AP.

Sum of AP is given by,

{n * (a + l) /2}           [Where a = first term, n = number of terms, l = last term.]

= 100 * (1 +100)/2 = 50 * 101.

Required Average = (50 *100)/100 = 50.5.

Short-Cut:

For an AP series,

Average = (first term + last term) /2

For above given series average,

= ( 1 +100)/2 = 50.5.