When using the normal approximation to the binomial distribution,which of the following is the correct range of x for finding the probability of getting 3 through 6 heads when tossing a coin 10 times?
A)x=3 through x=6
B)x=2.5 through x=6.5
C)x=3.5 through x= 6
D)x=2.5 though x=6

Question

Quizplus · Accepted Answer

When using the normal approximation to the binomial distribution, we need to use continuity correction. Therefore, we add 0.5 to the lower endpoint and subtract 0.5 from the upper endpoint. This gives us a range of x from 2.5+0.5=3 to 6-0.5=5.5. However, since we are looking for the probability of getting 3 through 6 heads, we need to add the probability of getting exactly 6 heads. Therefore, the correct range of x is 2.5+0.5=3 to 6+0.5=6.5, which is choice B.

When Using the Normal Approximation to the Binomial Distribution,which of the Following