Question

the sum of the first 6 terms of a geometric sequence is 7, 812. the common ratio is 5. what is the second term of the sequence?

a. 0.625

b. 10

c. 12.5

d. 30

Answer 1

OH right! I should have realised that!

S6 =  7,812 = a1 * (5^6 - 1)
                               -----------  were  a1 = first term
                                 5 -  1

3906*a1 = 7812
a1 = 7812 / 3906 =  2

Therfore the second term = 2*5  = 10 Answer