The sum of the first eight terms of an arithmetic progression is 220 if the third terms is 17.
Find the sum of the first six terms?
Why do you make it clear so that I can understand how to calculate
2 answers
8/2 (2a+7d) = 220
a+2d = 17
a=3 and d=7
That makes the sum you want
S6 = 6/2 (2*3+5*7) = ____
a+2d = 17
a=3 and d=7
That makes the sum you want
S6 = 6/2 (2*3+5*7) = ____
2 answers