Question

Question #24dc7

Answer 1

`C=r+s(t-3)`

Explanation:

The cost `C` of the call will be `r` cents for the initial 3 minutes plus the time `t` multiplied by the rate `s`.

Since you have already paid for the first three minutes, that time will need to be deducted from the overall time `t` before it is multiplied by the rate `s`.

So if `t>3`, your cost will be: #C=r+s(t-3)

Example: `t=5, r=$3, s=$2`

`C=$3+$2(5-3) = $3+$2xx2 = $3+$4 = $7`