It should be 64 since the square root of 64 is 8 and the cube of 64 is 4, which makes it a perfect square and perfect cube. I hope this helps. YOU'RE WELCOME :D
The first (80%) mortgage has an interest rate of 4.75%, and the second (20%) mortgage has an interest rate of 7.525%. Both are 30-year fixed-rate mortgages.
