SOLUTION: A basket contains red, blue and green balls. One ball is to be chosen at random. The probability that the selected ball is blue is equal to five times the probability that the sel

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Question 1192544: A basket contains red, blue and green balls. One ball is to be chosen at random. The probability that the selected ball is blue is equal to five times the probability that the selected ball is green. If The probability that the chosen ball is green is the same as the probability that the chosen ball is red, find the probability that the chosen ball is blue or red.
Found 2 solutions by greenestamps, ikleyn:
Answer by greenestamps(13203) (Show Source):
You can put this solution on YOUR website!

The probability that the selected ball is blue is equal to five times the probability that the selected ball is green.

So let P(green)=x; then P(blue)=5x.

The probability that the chosen ball is green is the same as the probability that the chosen ball is red....

So P(red)=x.

The sum of the probabilities is 1:

x+5x+x=1
7x=1
x=1/7

So
P(green) = 1/7
P(blue) = 5/7
P(red) = 1/7

ANSWER: P(blue or red) = 5/7 + 1/7 = 6/7

Answer by ikleyn(52824) (Show Source):
You can put this solution on YOUR website!
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A basket contains red, blue and green balls. One ball is to be chosen at random.
The probability that the selected ball is blue is equal to five times the probability
that the selected ball is green.
If the probability that the chosen ball is green is the same as the probability
that the chosen ball is red, find the probability that the chosen ball is blue or red.
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Let x be the probability that the randomly chosen ball is green. Then the probability that the randomly chosen ball is blue is 5x, and the probability that the randomly chosen ball is red is x. The sum of probabilities is 1 x + 5x + x = 1, which gives 7x = 1 and x= . Thus the probability that the randomly chosen ball is blue or red equals + = . ANSWER

Solved.