Question

peg and larry purchased "no contract" cell phones. Peg's phone cost $25 plus $0.25 per minute. Larry's phone cost $35 plus $0.20 per minute. After haw many minutes of use will Peg's phone cost more then Larry's phone?

Answer 1

Do you have a graphing calculator?

Answer 2

Solution:

Peg's phone cost $25 plus $0.25 per minute.

Larry's phone cost $35 plus $0.20 per minute.

Let Peg's phone cost more then Larry's phone after t minutes.

Then we can write

$25+0.25t=35+0.20t\\ \\ 35-25=0.25t-0.20t\\ \\ 10=0.05t\\ \\ t=200$

Hence Let Peg's phone cost more then Larry's phone after 200 minutes.