Question

1. The pollution level in the center of a city at 6 am is 30 parts per million and it

grows in linear fashion by 25 parts per million every hour. If y is pollution
and t is time elapsed after 6 am, determine:
a. The equation that relates y with t.
b. The pollution level at 4 o'clock in the afternoon​

Answer 1

a)
`y(t) = 30 + 25t`

b) The pollution level at 4 o'clock in the afternoon​ is of 280 parts per million.

Explanation:

The pollution level in the center of a city at 6 am is 30 parts per million and it grows in linear fashion by 25 parts per million every hour.

This means that the pollution in t hours after 6 am is given by:

`y(t) = 30 + 25t`, which is the answer to question a.

b. The pollution level at 4 o'clock in the afternoon​

4 in the afternoon is 10 hours after 6 am, so this is y(10).

`y(10) = 30 + 25*10 = 30 + 250 = 280`

The pollution level at 4 o'clock in the afternoon​ is of 280 parts per million.