An arithmetic series contains 20 numbers. the first number is 102. the last number is 159. which expression represents the sum of the series? a.(20 (159-102/2) b.(20(102+159/2) c.20(102+159) d.20(159-102)

Option B

Step-by-step explanation:

we know that

The sum of an arithmetic series is equal to

S=n(a1+an)/2

where

a1 is the first term

an is the last term

n is the number of terms

In this problem we have

n=20

a1=102

an=159

substitute the values in the formula

S=20(102+159)/2

exactly you go it

step-by-step explanation:

a

step-by-step explanation:

the denominator cannot be the same as one of the factors.

8 denominator times 2 denominator = 16

and 7 numerator time 11 = 77

77/16= 77/16 ( they cannot be further simplified)