Which is the verbal description?

Aball is dropped from a height of 10m above the ground. it bounce to 90% of its previous height on each bounce. what is the approximate height that the ball bounce to the fourth bounce?

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c

Solve this 364x-64x=300x and 12(x2–x–1)+13(x2–x–1)=25(x2–x–1)