Question

1.

A geometric series has first term 2 and sum to infinity 5.
1)Find the common ratio.

2)Find the sum of the first 10 terms of the series.

Answer 1

r = 3/5

Explanation:

S_∞ = a/(1 – r)

A geometric series has first term 2 and sum to infinity 5.

1)Find the common ratio.

= S_∞ = a/(1 – r)

5 = 2/1 - r

Cross Multiply

5(1 - r) = 2

5 - 5r = 2

5 - 2 = 5r

r = 5 - 2/5

r = 3/5

2)Find the sum of the first 10 terms of the series.

The sum of the first 10 terms =

S