SOLUTION: A jar contains 6 red marbles numbered 1 to 6 and 4 blue marbles numbered 1 to 4. A marble is drawn at random from the jar. Find the probability that the marble is blue or odd-numbe

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Question 1200243: A jar contains 6 red marbles numbered 1 to 6 and 4 blue marbles numbered 1 to 4. A marble is drawn at random from the jar. Find the probability that the marble is blue or odd-numbered.
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
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A jar contains 6 red marbles numbered 1 to 6 and 4 blue marbles numbered 1 to 4.
A marble is drawn at random from the jar. Find the probability that the marble is blue or odd-numbered.
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    P(blue or odd-numbered) = P(blue) + P(odd-numbered) - P(blue AND odd-numbered) = 

                            = 4%2F10 + %283%2B2%29%2F10 - 2%2F10 = 7%2F10.


Or mental reasoning says that there is 7 favorable marbles { 4 blue + disjoint 3 red odd-numbered }
of the total 6+4 = 10 marbles.

Solved in two different ways.