You have a cable plan that costs $39 a month for a basic plan plus one movie channel. your friend has the same plan plus two movie channels for $45.50. what is the basic plan charge that you both pay?

Let's break it down so we can see the difference

Basic cable + 2 movie = $45.50
Basic cable + 1 movie = $39.00

since difference means to subtract...the difference is $6.50 for 1 movie channel.
subtract the 6.50 from the rate of 39.00 and we get the true cost of basic cable$32.50

The answer would be b