A statistics question for you.
You have a 10-sided die with ONE 'YES' and NINE 'NO' outcomes (i.e. 10% chance of getting a 'YES').
If you roll the die 7 times, what is the probability that you get AT LEAST ONE 'YES' to come up?
Answers and explanations please. Thanks in advance.
2006-11-30 08:58:48 · 2 answers · asked by Sin™ 6 in Science & Mathematics ➔ Mathematics
This is the opposite of the probability of getting all no's. The probability of getting all No's is (9/10)^7. The probability of getting at least one yes is 1-(9/10)^7.
approximately 0.522
2006-11-30 09:02:50 · answer #1 · answered by Nicknamr 3 · 1⤊ 0⤋
Instead of computing P(1)+P(2)+...+P(10), compute P(0) and subtract it from 1.
P(0) = 7C0•(1/10)^0 •(9/10)^7
P(0) = 1 • 1 • 0.4783
P(0) = 0.4783.
So P(at least 1 "yes") = 1 - 0.4783 = 0.5217
2006-11-30 17:04:44 · answer #2 · answered by Philo 7 · 0⤊ 0⤋