Question

The cost of a long-distance phone call from Boston to London is defined by f(t) = 0.85(t -1) + 1.50, where the cost is $1.50 for the first minute and $0.85 for each additional minute. The cost of a five-minute phone call is
$ 3.40

$ 4.90

$ 5.75

$ 7.50

$ 9.60

Answer 1

The answer is $4.90 because if you multiply 5•.85 it equals $4.25 plus adding $1.50 subtracting the extra minute you first had to pay would give you $4.90