Question

A phone company charges customers a monthly charge using the equation C = 40 + 0.3m, where is the monthly

charge, in dollars, and m is the number of minutes used by the customer. If someone's monthly charge is $46, how
many minutes did the person use that month?
A. 5
B. 8
C. 10
D. 15
E. 20

Answer 1

Option E

The person used the phone for 20 minutes that month

Solution:

Given that phone company charges customers a monthly charge using the equation:

C = 40 + 0.3m

Where,

"C" is the monthly charge in dollars

"m" is the number of minutes used by the customer

Someone's monthly charge is $46

To find: number of minutes used by that person

Therefore, given C = 46

Substitute C = 46 in given equation

46 = 40 + 0.3m

40 + 0.3m = 46

0.3m = 46 - 40

0.3m = 6

`m = (6)/(0.3) = 20`

Thus the person used the phone for 20 minutes that month