Ann wants to choose from two telephone plans. Plan A involves a fixed charge of $10 per month and call charges at $0.10 per minute. Plan B involves a fixed charge of $15 per month and call charges at $0.08 per minute.
Plan A $10 + .10/minute
Plan B $15 + .08/minute
If 250 minutes are used:
Plan A: $10+$25=$35 Plan B: $15+$20=$35
If 400 minutes are used:
Plan A: $10+$40=$50 Plan B: $15+$32=$47
B is the correct answer. How to test it:
Plan A: $10+(.10*249 minutes) $10+$24.9=$34.9
Plan B: $15+(.08*249 minutes) $15+$19.92=$34.92
Plan A < Plan B if less than 250 minutes are used.
