Marsha has a bag that contains 4 green marbles, 8 yellow marbles, and 20 red marbles. if she chooses one marble from the bag, what is the probability that the marble is not red?

The probability is 0.375

Step-by-step explanation:

The probability is calculated as a division between the number of options that satisfy an specific condition and the total number of options. So, if Marsha choose one marble from the bag, she has 32 possible options:

From these 32 options, there are 12 that are not red:

Therefore, the probability P that the marble is not red is calculated as:

the simplified form is

step-by-step explanation:

we want to simplify the expression,

let us change the middle bar to a normal division sign to obtain,

we multiply the first fraction by the reciprocal of the second fraction to obtain,

we factor to obtain,

we cancel the common factors to get,

we simplify to get,

the correct answer is b