Answer:
15
Step-by-step explanation:
The formula for factoring a sum of cubes is:

We have a=3f and b=5g here.
So a*b in this case is 3f*5g=15fg.
The ? is 15.
all u are doing is adding them up
The answer to the question :) 17/40=.425
6w is the 6 times a length w