+55 In the SuperLottery, three balls are drawn (at random) from ten white balls numbered from $1$ to $10$, and one SuperBall is drawn (at random) from ten red balls numbered from $11$ to $20$. When you buy a ticket, you choose three numbers from $1$ to $10,$ and one number from $11$ to $20$. If the numbers on your ticket match the three white balls and the red SuperBall, then you win the jackpot. (You don't need to match the white balls in order). What is the probability that you win the jackpot?
+37153 Here is my take on this one:
Try again:
Re-take:
How many possible combos are there?
10 c 3 * 10 C1 = 1200 possible combos you have a 1 in 1200 chance of doing this
Matching two AND Superball
10 c 2 = 45
10 c 1 = 10 (for Superball) 45 * 10 = 450 you have a 450 out of 1200 chance of doing this
Matching two
45 out of 1200
matching three
120 out of 1200
matching superball
10 out of 1200
total prob of winning is then (1 + 450 + 45 + 120 + 10)/1200 = 626/1200 = 313/600
Hmmmmm.....getting closer perhaps!
+129899 We have two tasks.....choose the correct white balls and choose the correct SuperBall
Number of possible sets of C(10,3) = 120.....only one of these will win
So 1/120
And the probability of choosing the correct SuperBall = 1/10
So
(1/120) * (1/10) = 1 /1200
+37153 TRY number THREE:
1200 possibles 1 / 1200 chance to match that exactly
1 / 10 chance to match only superball 10 out of 1200
1 / 120 chance to match all 3 whites 10 out of 1200
3 ways to match 2 out of three whites 3 out of 1200 you could hit the superball too ( + 3/1200* 1/10 ?)
1 + 10 + 10 + 3 / 1200 = 24/1200 1/50 chance of a wining ticket so far....but I do not know how to compensate for the red note above
