15+ .12x = 18 + .09x
.03x = 13
Can you solve it from here?
Divide both sides by .03
.03x = 13
Can you solve it from here?
Divide both sides by .03
Let's say the number of minutes used is represented by "m."
For Sally's cell phone company, the cost is a flat rate of $15.00 per month plus $0.12 per minute. So the total cost for Sally's plan can be calculated as:
Total cost for Sally's plan = Flat rate + (Cost per minute × Number of minutes)
Total cost for Sally's plan = $15.00 + ($0.12 × m)
For Eduardo's cell phone company, the cost is a flat rate of $18.00 per month plus $0.09 per minute. So the total cost for Eduardo's plan can be calculated as:
Total cost for Eduardo's plan = Flat rate + (Cost per minute × Number of minutes)
Total cost for Eduardo's plan = $18.00 + ($0.09 × m)
Now, we want to find the number of minutes "m" for which the total costs for both plans are equal. So we can set up the following equation:
$15.00 + ($0.12 × m) = $18.00 + ($0.09 × m)
To solve this equation, we can subtract $15.00 from both sides and subtract $0.09 × m from both sides:
$0.12 × m - $0.09 × m = $18.00 - $15.00
Simplifying, we get:
$0.03 × m = $3.00
Now, we can divide both sides by $0.03 to solve for "m":
m = $3.00 / $0.03
m = 100
Therefore, you would have to use 100 minutes for the price to be the same for both plans.