SOLUTION: A jar contains a red marble, a blue marble, and six green marbles. Tom draws one marble from the jar, and then Mary draws a marble from those remaining. If the probability that Tom

Algebra ->  Probability-and-statistics -> SOLUTION: A jar contains a red marble, a blue marble, and six green marbles. Tom draws one marble from the jar, and then Mary draws a marble from those remaining. If the probability that Tom      Log On


   

Question 300242: A jar contains a red marble, a blue marble, and six green marbles. Tom draws one marble from the jar, and then Mary draws a marble from those remaining. If the probability that Tom draws the red marble and Mary draws the blue marble is 1/x,
what is the value of x?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1 R, 1 B, 6 G, 8 total
Probability that Tom picks a red=1/8.
0 R, 1 B, 6 G, 7 total
Probability that Mary picks a blue=1/7.
Both together, multiply the probabilities.
P=%281%2F8%29%281%2F7%29=1%2F56
x=56