# Pasta hypothesis

superwolf
According to a marketing expert, 40% of Pastafarians prefer lasagna. If 9 out of 20 pastafarians choose lasagna over other pastas, what can be concluded about the expert's claim? Use a 0.05 level of significance.

Attempt:

H0: p=0.4
H1: p=/=0.4

Test statistic: Binominal variable X with p=0.4 and n=20.

x=9, and np0 = 8

$$P=1 - \Sigma_{x=0}^9 b(x;20,0.4) = 1 - 0.7553 = 0.2447$$

??

Last edited:

Homework Helper
You have to add the probabilities for 9, 10, 11, ...., 20. That is the complement (1 - ...) of what?

In other words, you want to calculate the probability that nine or more would prefer the lasagna, which is less than how many?

Mentor
According to a marketing expert, 40% of Pastafarians prefer lasagna. If 9 out of 20 pastafarians choose lasagna over other pastas, what can be concluded about the expert's claim? Use a 0.05 level of significance.

Attempt:

H0: p=0.4
H1: p=/=0.4

Test statistic: Binominal variable X with p=0.4 and n=20.

x=9, and np0 = 8

$$P=1 - \Sigma_{x=0}^9 b(x;20,0.4) = 1 - 0.7553 = 0.2447$$