Bill wants to see how many times he needs to roll a standard number cube before getting a 5. What is the probability that Bill w

Question

3 years ago

14

ill roll a 5 on his third roll and not before?
a. 125/1296
b. 25/216
c. 1/6
d. 1/2

2 answers:

chubhunter [2.5K] · Answer 1 · 2022-05-11T06:42:03+03:00

5 0

5/6 • 5/6 • 1/6 = 25/216 the answer is b

Hoochie [10] · Answer 2 · 2022-05-11T07:58:21+03:00

4 0

Answer:

The answer is b. 25/216

Step-by-step explanation:

Bill wants to see how many times he needs to roll a standard number cube before getting a 5.

p = $\frac{1}{6}$ (on an average: roll 6 times before getting a 5)

The required probability can be found as :

$\frac{1}{5}(\frac{5}{6}* \frac{5}{6}* \frac{5}{6})$

= $\frac{5}{6}* \frac{5}{6}* \frac{1}{6}$

= $\frac{25}{216}$

So, the answer is b. 25/216