Q:

For the spinner above, the probability of landing on black is 1/2 and the probability of landing on red is 1/3. Suppose is is spun four times. What is the pobability that it will land on white all four times?A. 1/216B. 1/24C. 1/4096D. 1/1296My answer was A. 1/216 but, that was wrong. Cant figure this out. I always hated doing probability questions...

Accepted Solution

A:
First, we need to figure out the probability of landing on white one time. The probability of landing on black is 1/2, and the probability of landing on red is 1/3. If we add these probabilities together we get:

[tex] \frac{1}{2}+ \frac{1}{3} = \frac{3}{6}+ \frac{2}{6} = \frac{5}{6} [/tex]

So if there is a 5/6 chance of NOT landing on white, then there must be a 1/6 chance of landing on white.

To find the probability of landing on white 4 times, multiply 1/6 to itself 4 times.

[tex]( \frac{1}{6})^4 = \frac{1}{1296} [/tex]

The answer is D.