Question

Determine the sum of the arithmetic series 6 + 11 + 16 +......
91.

Answer 1

Answer:

873

Step-by-step explanation:

so the equation is: 5x+1

sum is:

$\frac{first \: one \: + \: last \: one}{2} \times quantity \: of \: terms$

we have 6( 5×1+1) to 91 (5×18+1)

so we have 18 terms

then:

$\frac{91 + 6}{2} \times 18 = 873$