Question

The sum of the even integers between 21 and 81

Answer 1

22,24,26........80
ita an arithmetic sequence :)

Answer 2

how do you get the sum?

Answer 3

Srrry idk =0

Answer 4

use the formula :
\(\Large S_n = n/2 (2a+(n-1)d)\)

familiar with this formula?

Answer 5

n is the number of terms that you need to find out first

a = 1st term
d = common difference

Answer 6

thanks !

Answer 7

you can use the sequence
a(n) = 2n + 20

Answer 8

a(1) = 2*1 + 20 = 22
a(30) = 2*30 + 20 = 80