The ratio of blue and green marbles is 5:6. If there are 40 blue marbles, how many green marbles are there?

If 1 is divided by the sum of y& 4. the result is equal to 3 divided by 4 .find the value of m?

Suppose i flip two identical coins. what is the probability that i get one head and one tail?

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?