Question

About 12 weeks ago, there were 21 mold spores found in a garden. After a few weeks of observation, it is determined that the number of mold spores in the garden is tripling every 6 weeks. The number of mold spores, M, at any given time in the garden is equal to the product of the initial amount of spores, I, and 3 to the power of n, where n is the number of times the amount of mold spores has tripled. How many mold spores are in the garden today?

Answer 1

189 spores

Explanation:

The number of mold spores triple every 6 weeks. So in 12 weeks, it has tripled twice.

Given that:

M = I x
`3^(n)`

where M is the number of mold spore, I is the initial amount of spores, and n is the number of times the amount of mold spores has tripled.

Since, I = 21 and n = 2, we have;

M = 21 x
`3^(2)`

= 21 x 9

= 189

There would be 189 spores in the garden today.