Question

There is a bag filled with 3 blue and 4 red marbles.

A marble is taken at random from the bag, the colour is noted and then it is replaced.
Another marble is taken at random.
What is the probability of getting 2 reds?

Answer 1

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Explanation:

The probability of getting 1 red is 4/7. The probability of getting 2 reds in a row is (4/7)^2 = 16/49.