A fair die is rolled 50 times. Find the probability of observing:
a) exactly 10 sixes
b) no more than 10 sixes
c) at least 10 sixes
I know how to do
a) $\frac{50!}{10!(40!)}$x$(\frac{1}{6})^{10}$x$(1-\frac{1}{6})^{50-10}$
=0.1155
Please help me out to do b) & c) I have tried same formula above and changing power to 9, 11 etc…
But Can't get right answer.!
Appreciate your help!
Best Answer
Hint: You will get no more than 10 sixes if you get no sixes or one six or two sixes or three sixes or ... or nine sixes. Since these possibilities are mutually exclusive, you can add the individual probabilities to get the total probability.
Once you've solved (b), think how you can use that answer to solve (c).