Felipe surveyed students at his school. He found that 78 students own a cell phone and 57 of those students own an MP3 player.
There are 13 students that do not own a cell phone, but own an MP3 player.
Nine students do not own either device.

A two way table for the above information is given below:


Find the value of a, b, c, d and e.

a =

b =

c =

d =

e =