Greg has 1/4 as many songs on his computer as mark. Raj has 6 fewer than 60% of the songs that mark has. Mark has 720 songs on his computer.

Greg has 180 songs on his computer

Raj has 426 songs on his computer

Mark has 720 songs on his computer

Step-by-step explanation:

First you find out how much songs Greg has. He has 1/4 as many as mark so 720 x 1/4 = 180. This is because 720 x 1/4 is the same as 720/4. Now we know that Greg has 180 songs on his computer. Next, Raj has 60% of the songs Mark has so 60% of 720 is 432. Because he has 6 fewer than 60%, 432-6=426.

Therefore,

Greg has 180 songs on his computer

Raj has 426 songs on his computer

Mark has 720 songs on his computer

Hope this helps