Suppose that x varies directly with y and x=17 when y=-85. what is the constant variation and what is the value of x when y=-160

Some boys and girls were asked if they had a pet. one third of the group were boys. there were 20 boys. 20% of the girls had a pet. boys with a pet : girls with a pet = 1 : 5 i need to know how many girls there are.

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?

Set up and solve a proportion for the following application problem. if 55 pounds of grass seed cover 404 square feet, how many pounds are needed for 7272 square feet?