Question

4.What is the sum of an 8-term geometric sequence if the first term is 10 and the last term is
781,250?
i need help findng the common ratio ? please

Answer 1

8th term = ar^7 and first term = a
r^7 = = ar^7 / a = r^7 = 781250 / 10 = 78125
r = seventh root of 78125 = 5
common ratio = 5

Answer 2

can you calculate the sum?

Answer 3

yes i just needed help finding the common ratio, thank you soo much

Answer 4

yw