Question

Finding the final amount in a word problem on continuous exponential growth or decay

Answer 1

Given:

The mass of radioactive follows an exponential decay model

The initial mass = 418 kg

Decreases at a rate = r = 4% per day

So, the general formula for the mass will be:

`m=418\cdot(1-0.04)^d`

where: (m) is the mass after (d) days

So, to find the mass after 2 days, we will substitute with d = 2

so,

`m=418\cdot(1-0.04)^2=418\cdot0.96^2=385.2288`

rounding to the nearest tenth

so, the answer will be mass after 2 days = 385.2 kg