SOLUTION: THERE IS A BAG FILLED WITH 5 BLUES AND 4 RED MARBLES. A MARBLE IS TAKEN AT RANDOM FROM THE BAG,THE COLOR IS NOTED AND THEN IT IS REPLACED. ANOTHER MARBLE IS TAKEN AT RANDOM. WHA

Question 1154968: THERE IS A BAG FILLED WITH 5 BLUES AND 4 RED MARBLES.
A MARBLE IS TAKEN AT RANDOM FROM THE BAG,THE COLOR IS NOTED AND THEN IT IS REPLACED.
ANOTHER MARBLE IS TAKEN AT RANDOM.
WHAT IS THE PROBABILITY OF GETTING EXACTLY ONE BLUE?

Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!



Hi  

 9 Marbles: 5B & 4R

two draws (with replacement)

P(exactly one blue) = P(BR) + P(RB)=  [(5/9)(4/9)+ (4/9)(5/9)] 

P(exactly one blue)= [40/81] = 40/81

0r

P(exactly one blue) = 1 - P(RR)  - P(BB)

1 - 25/81 - 16/81 =  1- 41/81 = 40/81

Try to have some fun with these.. 

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