Can someone check my work please?
Fine the sum of the arithmetic series -4 + 1 + 6 + 11 + ..... + 91.
I know that a1= -4, d=5, and a20=91.
S20= 20/2 (-4 + 91)
S20= 10 (87)
S20= 870
The sum of the arithmetic series is 870.
2 answers
Your work is completely correct.
Yay!! Thank you so much for checking. Have a lovely day.
2 answers