I don’t understand this at all

You are remodeling your kitchen. you’ve contacted two tiling companies who gladly told you how long it took their workers to tile of a similar size jim completed half the floor in 8 hours. pete completed half of the other floor in 7 hours. if pete can lay 20 more tiles per hour than jim, at what rate can jim lay tiles

I'm confused on this could anyone me and show me what i need to do to solve it.

Interpret the following expression (5y^2-7)^3/(2y)^2