Courtney's summer camp has 2 canoes for every 5 campers. If there are 70 campers in all, which proportion can be used to calculate how many canoes there are at the camp?​

Large circle circumference  =  34.5575 units =large circle  diameter = 11 unitsmiddle circle  diameter =  8 unitssmall circle  diameter = 5 unitsarea of shaded region = middle circle area -small circle areaarea of shaded region =  pi * 8 ^2 / 4   minus pi * 5^2 / 4area of shaded region =  50.27 -19.63area of shaded region = 30.64 square units