The most points Sidney has scored in a basketball game is 282828. She is trying to tie that record in her current game. Write an equation for the number of points Sidney needs to score to tie her record, rrr, if she has already scored ppp points.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?