Nicole pulls a colored marble out of a bowl, choosing the marble at random. There are 120 marbles in the bowl, of which 80 are black, 28 are white, and the rest are red. Use words and numbers to describe the probability that she will pull a red marble out of the bowl. Show your work
The total number of marbles in the bowl is 120. Of these, 80 are black, 28 are white, and the rest are red.
To calculate the probability of Nicole pulling a red marble, we first need to determine how many red marbles are in the bowl. Since 80 marbles are black and 28 are white, the number of red marbles can be found by subtracting the sum of black and white marbles from the total number of marbles:
Number of red marbles = Total number of marbles - number of black marbles - number of white marbles
Number of red marbles = 120 - 80 - 28
Number of red marbles = 12
Therefore, there are 12 red marbles in the bowl.
The probability of Nicole pulling a red marble can be calculated by dividing the number of red marbles by the total number of marbles in the bowl:
Probability of red marble = Number of red marbles / Total number of marbles
Probability of red marble = 12 / 120
Probability of red marble = 1 / 10
Probability of red marble = 0.1
Therefore, the probability of Nicole pulling a red marble out of the bowl is 0.1 or 10%.