John has a total of 72 points out of 90 possible in his history class. his final exam is worth 10 points. how many points must he get on his final exam to end the class with a 80%?

You are cycling around europe with friends. you book into a hostel and you ask the owner what the ratio of men to women is currently staying there. there are 24 men and 6 women. what is the ratio of men to women in its simplest form?

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?

Cole says the distance between points (-5,0) and (0,-5)is 5 units. is he correct? explain why or why not.