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3 years ago

5

Gina has a jar of marbles that contains 7 blue marbles, 5 red marbles, and 8 green marbles. She randomly selects a marble, recor

ds the color, and places the marble back into the jar. She then selects another marble. What is the probability that Gina randomly selected two red marbles. ( fraction in simplest form )

1 answer:

BigorU [14]3 years ago

6 0

The probability that Gina randomly selected two red marbles is 1/19

<u>Explanation:</u>

Total number of marbles = 7 + 5 + 8

= 20

The probability of getting two red marbles in the fraction form is given as:

P(first red marble) = number of red marbles / total number of marbles

P(first red marble) = $\frac{5}{20} = \frac{1}{4}$

P(second red marble) = number of red marbles after 1 white marble is removed / total number of marbles after 1 red marble is removed.

P(first red marble) = $\frac{4}{19}$

P(two red marbles) = P(first) X P(second)

= $\frac{1}{4} X \frac{4}{19}$

= $\frac{1}{19}$

Therefore, the probability that Gina randomly selected two red marbles is 1/19

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