The tape diagram represents the ratio of the time you spend tutoring to the time your friend spends tutoring. You tutor for 3 hours. How many hours does your friend spend tutoring?

By a quick online search, i found two tape diagrams:

13) You: -

     Friend: - -

So you have one block, and your friend has two.

We know that you work for 3 hours, this means that your only block must represent 3 hours.

And all the blocks represent the same amount of time, then each one of the two blocks of your friend also represents 3 hours.

Then in total, he tutored for 3 hours + 3 hours = 6 hours.

14) You: -

     Friend: - - - - -

In this case, you still have only one block, but now your friend has 5.

Using the same reasoning as above, we can conclude that each block represents 3 hours, and your friend has 5 of them, this means that he tutored for:

5*3 hours = 15 hours

i would say c is the best answer, hope it's right!

good luck! =)

cutie~