Phil is riding his bike. He rides 58 miles in 4 hours, 72.5 miles in 5 hours, and 87 miles in 6 hours. Find the constant of proportionality and write an equation to describe the situation. Let x represent the number of
hours.
The constant of proportionality is k =
The equation that describes the relationship is y =

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?