Problema Solution

15 marbles are placed in a bag; some are red and some are blue. If the number of red marbles is 1 more than the number of blue marbles, what is the probability that a marble taken from the bag is blue?

Answer provided by our tutors

Let 'x' the number of blue marbles and 'x + 1' the number of red marbles.

x + (x + 1) = 15

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click here to see the equation solved for x

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x = 7 blue marbles

The probability that a marble taken from the bag is blue is:

P(the marble is blue) = 7/15

P(the marble is blue) = 0.4667