Verified answer

use the formula

sn=n/2(2a+(n-1)d)

here n=10

a=2

d=5

s10=10/2*[(2(2)+(10-1)5)]

=5(4 + (9*5))

=5(4+45)

=5(49)

=245 <=== answer

A.245

a=-6

d=2

s22=22/2*(2(-6)+(22-1)2)

=11*(-12+42)

=11*30

=330

just use formula and find the answer :)

Find S10 for the series 2 + 7 + 12 + 17 +…?

A.245

Find S22 for -6 + (-4) + (-2) + 0 …?

A.330

the first one you just keep adding 5 to the previous number

7 + 5 = the 12

12+ 5 = the 17

17+ 5 = the 22

keep doing this until you have 10 integers, then you fine the sum of them all

the second one is the same type of problem.

find the pattern until you get to the 22nd integer and solve it