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MATH / In a bag with 20 marbles, five of them are blue. How many blue marbles must be…

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problem

In a bag with 20 marbles, five of them are blue. How many blue marbles must be added to the bag so that the probability of selecting a blue marble at random is 12\frac{1}{2}?
Plain-text mathematical notation (without MathML)
In a bag with 20 marbles, five of them are blue. How many blue marbles must be added to the bag so that the probability of selecting a blue marble at random is (1)/(2)?
Original LaTeX notation
In a bag with 20 marbles, five of them are blue. How many blue marbles must be added to the bag so that the probability of selecting a blue marble at random is $\frac{1}{2}$?

level

Level 2

type

Prealgebra

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