Math word problem?............?
one cell phone costs $39.95 per month.
the first 500 minutes of usage are free.
each minute after costs $0.35.
for a bill of $69.70 , how many minutes over 500 minutes was the cell phone in use?
Update:im confused i no now dat da answer is
85 but how do u get dat? wats da equation ?
Comments
69.70 = 39.95 = 29.75, which is the cost of the minutes over 500
$29.75 divided by $0.35/minute = 85 minutes
So 85 minutes over 500 was used, which makes 585 minutes in total
Actually the first 500 minutes are not free -- you paid $39.95 for them! They are "without additional cost." I am not being fussy. Saying it correctly helps you visualize the situation in a way that you can quantify it.
So minutes OVER 500 ARE CHARGED AT $0.35, so if x= chargeable minutes used, your equation in woirds is
Total Cost = 39.95 + .35(chargeable minutes) Or in tems of x:
Cost = 39.95 + .35x But Cost = 69.70, so
69.70 = 39.95 + .35x. Solving for x:
29.75 = .35x (Divide by .35)
85 = x = number of minutes over 500
69.70 - 39.95 = 29.75 = usage cost
29.75 / .35 = 2975 / 35 = 85
85 additional minutes beyond the 500 free minutes
85 * .35 = 29.75 +39.95 = 69.70 total bill
69.70-39.95=29.75
29.75/0.35=85 minutes over 500
excess charge=69.70-39.95=$29.75
excess minutes=excess charge/minute cost
=29.75/.35=2975/35
=595/7=85minutes
85 min.