I want detail answer

Question

You are choosing between two different cell phone plans. The first plan charges a rate of 20 cents per minute. The second plan charges a monthly fee of $34.95 plus 10 cents per minute. How many minutes would you have to use in a month in order for the second plan to be preferable?

Answer 1

.20m = 34.95 + .10m

.10m = 34.95

m =34.95/.10 = 349.5 minutes usage makes the two plans cost the same

use less than 349.5 minutes and the First Plan is less expensive

use more than 349.5 minutes and the Second Plan is less expensive

try 350 minutes

.20(350) = 34.95 + .10(350)

70 = 34.95+35 = 69.95

70>69.95, 2nd Plan is cheaper for over 349.5 minutes