World Problem - Help (which phone card to use? why?)

I need to find a step by step solution to this problem English language that I can understand.


A convenience store advertised two phone cards. Which card would you buy ? Why?

Card 1: 3.9 cents a minute with 37 cents connection chatrge for each call.

Card 2: 7.9 cents a minute with no connection charge.

How much would each card charge for one minute of use? Two minutes? Three minutes? Ten minutes? Fifteen?

Keep going until you have enough data to draw a conclusion regarding the duration of call for which each card would be best. You'll want to include in your discussion of "why" your thoughts regarding your "usual" call length.

Eliz.