Question

The faces of an 8-sided die are numbered from 1 to 8. What is the probability of rolling a 5 three times in ten rolls?

Answer 1

\[P(three\ 5's\ out\ of\ 10\ rolls)=10C3\times (\frac{1}{8})^{3}\times (\frac{7}{8})^{7}\]

Answer 2

Okay! You dont have to do it for me, but how do I go about doing the multiplication for 1/8 to the power of three?

Answer 3

Would it look like this? P(x=3) = \[10C3(0.1)^{3}(0.7)^{8} \] ?

Answer 4

Turn the fractions into decimals:
1/8 = 0.125
7/8 = 0.875
So the required probability is given by the following:
\[120\times (0.125)^{3}(0.875)^{7}\]