Cell phones
Let f(t) be the number of people, in millions, who own cell phones t years after 1990. Explain the meaning of the following statements.
- f(10)=100.3
- f(a) = 20
- f(20) = b
- n=f(t)
Let f(t) be the number of people, in millions, who own cell phones t years after 1990. Explain the meaning of the following statements.