Question

a glass jar contains 1 red, 3 green, 2 blue, and 4 yellow marbles. if a single marble is chosen at random from the jar, what is the probability that it is red

Answer 1

To find the probability, you need to divide the amount of red marbles by the total amount of marbles. 

1/10 = 0.1. 

The probability of choosing a red marble is 0.1, or 10%

Answer 2

$|\Omega|=10\\ |A|=1\\\\ P(A)=\dfrac{1}{10}=10\%$