Question

What was the first year that the amusement park had more than 12 million visitors?

Answer 1

The first year that the amusement park had more than 12 million visitors is 2008.

Explanation:

Given:

`y=4.2√(0.28x-1)`

As per the question, the number of visitors must be greater than 12 million.

So,
`y>12`

Plug in
`4.2√(0.28x-1)` for
`y` and solve for
`x`.

`4.2√(0.28x-1)>12`

`√(0.28x-1)>(12)/(4.2)\\0.28x-1>((12)/(4.2)) ^(2) \\0.28x>8.16+1\\x>(9.16)/(0.28) \\x>32.7\\`

Therefore, least value of
`x` for which the number of visitors are more than 12 million is
`x=33`.

Since,
`x` is measured after 1975.

Therefore, the first year that the amusement park had more than 12 million visitors is
`1975+x=1975+33=2008`.