Problema Solution

your monthly cell phone bill $65 per month plus and additional charge of $0.15 per minute. If you go over the 1000 minutes included in the plan. If your cell phone bill was $200 last month, how many extra minutes did you use?

Answer provided by our tutors

200 = 65 + 0.15(x-1000)

200 - 65 = 0.15(x-1000)

135/0.15 = x - 1000

900 = x - 1000

x = 1900

so extra minute used =  900