Answer: 77 CD’s
Step by step:
Since we are writing a proportion it will look like this .....
33/1.5 = x/3.5 ( 33 over 1.5 and x over 3.5)
Now that we have our proportion , you cross multiply.....
33 x 3.5 = 115.5
“X” x 1.5 = 1.5x
So now you will have an equation that looks like this....... 1.5x=115.5
Once you have that then you divide 1.5 from each side , then after that then you should have x=77
So it takes 77 CD’s to be in a 3.5 inch high stack .
Hoped this helped , if it didn’t I apologize
Good luck