Question

Roberto notices that his hair is decreasing exponentially at a rate of 60% per year. If he starts with 100,000 hairs on his head,how many hairs will he have after 4 years? worth 98 points! please help!

Answer 1

100,000(1-0.6)

Total: 2560

Explanation:

P = 100,000, r = - 60 % = -0.6 x = 4

Answer 2

2560 hairs.

Explanation:

Given,

The initial number of hairs, P = 100,000,

The rate of change per year, r = - 60 % = -0.6 ( Negative sign shows decreasing )

Thus, the population after x years,

`A=P(1+r)^t`

`=100,000(1-0.6)^x`

`=100,00(0.4)^x`

Which is the function formula for the given scenario,

When, x = 4 years,

The number of hairs after 4 years would be,

`A=100,000(0.4)^4`

`=100,000* 0.0256`

`=2560`