Probability question

Question

A box contains 5 blue beads 4 yellow beads and 3 purple beads . Three beads are taken at random without replacement .what is the probability of picking in order a blue bead followed by a yellow bead followed by a purple bead 

 

Answer 1

Hi James,

 

any of these probabilities = (the number of beads of that color in the box)/(total beads in the box)

 

The P(blue) =5/12

 

Now 1 bead has been taken out so there are 11 remaining

 

P(yellow) = 4/11

 

Now 2 beads have been taken out so there are 10 remaining

 

P(purple) = 3/10

 

P(blue, yellow, purple) = (5/12)(4/11)(3/10)

 

P(blue, yellow, purple) =60/1320

 

 = 1/22 = approximately .045

 

but the fraction is the exact answer