Question

A blogger had 400 subscribers to her blog in January. The number of subscribers has grown by a factor of 1.5 every month since then. Write a sequence to represent the number of subscribers in the 3 months that followed.

Answer 1

`600, 900, 1350`

Explanation:

Given

`a = 400` -- initial subscribers

`b = 1.5` -- growth factor

Required

Determine the number of subscribers in the next three months

To do this, we make use of:

`y = ab^x`

In this case:

x is the number of months

y is the number of subscribers

So:

when x = 1;

`y = ab^x`

`y = 400 * 1.5^1`

`y = 400 * 1.5`

`y = 600`

when x = 2

`y = 400 * 1.5^2`

`y = 400 * 2.25`

`y = 900`

when x= 3

`y = 400 * 1.5^3`

`y = 400 * 3.375`

`y = 1350`

So, the next three number of subscribers is:

`600, 900, 1350`