Question

A telephone company charges $0.30 for the first 4 minutes of a call and $0.18 for each additional minute. How long can a person talk for $3

Answer 1

x= total minutes -4    the 1st 4 minutes are included in the .30

total cost = .3 + .18 x  

3 = .3 +.18 x

subtract .3 from each side

2.7 = .18x

divide by .18 on each side

2.7/.18 = x

15 = x

x = total minutes -4

add 4 to each side

15+4 = total minutes

they can talk 19 minutes