Question

A bag contains 5 red marbles, 6 blue, 3 green, 4 black, and 2 yellow. If a marble is drawn from the bag and replaced 100 times, then what is a reasonable prediction for the number of times a green or black marble will be drawn?

Answer 1

So there are 20 marbles in the bag, and there are 3 green.
So let's write the expression as:
3/20.
So if you draw the marble one time you have a 3 in 20 chance of drawing a green marble.

Now since we are drawing the marble from the bag 100 times, let's convert 3/20 in terms of 100.

To do such you need to find a number that can multiplied by 20 that will get you 100.

20 x 5 = 100

So what ever we do to the bottom we do to the top.
So let's multiply 5 by our numerator 3.
You should get 15.

So if you draw a marble out of a bag 100 times, you will have a 15/100 chance you'll draw a green marble.
Thus, the green marbles could be drawn 15 times.