the 6 term of a G.P is 2000 its common ratio is 10 find the first term?

1 answer

a1 = initial value

r = common ratio = 10

The n-th term of a geometric sequence:

an = a1 * r ^ ( n - 1 )

In this case:

a6 = a1 * r ^ 5

2,000 = a1 * 10 ^ 5

2,000 = 100,000 a1 Divide both sides by 100,000

2,000 / 100,000 = a1

0.02 = a1

a1 = 0.02