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3 years ago

6

A jar contains only black and white marbles. When one marble is drawn at random, the probability that it is white is 1/3. After

20 black marbles were added to the jar, the probability of drawing a white was 1/5. How many marbles were in the jar originally?

1 answer:

KonstantinChe [14]3 years ago

6 0

there are 30 marbles in the jar originally

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