Problema Solution
Susan subscribes to an online computer service that charges $9.50 per month for 30 hours online and $1.50 for each hour online in excess for 30 hours. Last month her bill was $20. How many extra hours was she charged for?
Answer provided by our tutors
Given this, monthly bill will be
: y = 9.5 + 1.5x
20 = 9.5 + 1.5x
10.5 = 1.5x
x = 7 extra hours