Find the sum of the following without actually adding: 1+3+5+7+9+11+13+15

use this formula Sn=n/2[2a+(n-1)d]

here,d=a2-a1 and n= no. Of terms

Step-by-step explanation:

S8=8/2[2(1)+(8-1)2]

S8=64

Step-by-step explanation:

The following numbers are successive odd numbers.

The sum of successive odd numbers (starting from 1) is always the square of number of terms you are adding.

Hear there are 8 terms. Square of 8 is 64.

Hence the sum of this numbers is 64.

is there answer choices?

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.