Question

Two phone companies one is 11/+.16/ min And another is 20+.11/min How many minutes will make both equal amounts

Answer 1

Company one charges $11 + $0.16 per min.

Then if you talk for x minutes, the cost will be:

C₁(x) = $11 + ($0.16 per min)*x

For company two, the prize is $20 + $0.11 per min, and if yo talk for x minutes, the cost will be:

C₂(x) = $20 + ($0.11 per min)*x

Now we want to find the value of x, the number of minutes, such that the cost is the same with both companies.

C₁(x) = C₂(x)

$11 + ($0.16 per min)*x = $20 + ($0.11 per min)*x

($0.16 per min)*x - ($0.11 per min)*x = $20 - $11

($0.05 per min)*x = $9

x = $9/($0.05 per min) = 180 mins

If you speak for 180 minutes, the cost is the same in both companies.