Answer:
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