Question

The population of a city, P , in millions, is a function of ????, the number of years since 2010, so P = ???? (????). Explain the meaning of the statement ????(5) = 7 in terms of the population of this city.

Answer 1

The population of city is 7 million in 2015.

Explanation:

It is given that the population of a city, P, in millions, is a function of t, the number of years since 2010.

It means, P = f(t).

We need to explain the meaning of the statement f(5) = 7 in terms of the population of this city.

f(5) = 7 means the population is 7 millions at t=5.

t = 5 means 5 years after 2010, i.e., 2010+5 = 2015

Therefore, the population of city is 7 million in 2015.