What is the sum adding numbers 1 through 100?

101* 50 = 5050

0 + 100 = 100

1 + 99 = 100

...

49 + 51 = 100

(50 x 100) + 50 = 5050

Or another way:

1 + 100 = 101

2 + 99 = 101

...

50 + 51 = 101

50 x 101 = 5050

use gauss' formula

sum of numbers 1 through x = x(x+1)/2

so 100*101/2=5050

yes he is correct. There are 49 pairs of numbers that add up to 100, and then 100 and 50 is left over, giving you 5050.

Add 1+99, 2+98, 3+97,... until 49+51,

therefore 49 X 100 = 4,900

Then add 50 & 100, i.e 4,900+100+50 = 5,050.

if you add 1 & 100= 101. if you add 1 - 100 you get 13293.

that is arithmetic sequence

the sum for this sequence is

S=(n/2)*(a1+an)

n= how many of them=100

a1 = first term= 1

an=last term =100

so sum is

S=100/2*(1+100)

S=50*101=5050

good luck

The right answer, naturally, is 5050.

5050

5050