phone bill

Question

David pays a $7 monthly fee plus cents 7 per minute. Last month, David's long distance bill was $20.44 . For how many minutes was David billed?

Answer 1

Suppose X minutes was David billed.

 

7 cents  per minute = $0.07/minute, So, X minute cost $0.07 X.

$7 + $0.07 X = $20.44

$0.07 X = $13.44 (subtract $7 for both sides)

X = 192 (minutes)

Answer 2

m represents the number of minutes

20.44 = 7 + 0.07m

 

Can you solve for m and answer?