3/20 is the same as 15/100 or 15%
so 10×3/20 would be the same as 10×15% or 150%
Is that what you were asking?
Answer:
part 1= "72=(2w)+(w-15)"
part 2= "29"
I'm not sure if they want "w = abc"
I used that equation to solve part 2
Hope this helps you, I've been where you are
Yes compund interest is always greater than simple interest
simple interest = principal
compound interest = principal + accumulated interest