Question

A genetic experiment with peas resulted in one sample of offspring that consisted of 427 green peas and 154 yelow peas. a. Construct a 90% confidence interval to estimate of the percentage of yellow peas. b. Based on the confidence interval, do the results of the experiment appear to contradict the expectation that 25%, of the offspring peas would be yellow? a. Construct a 90% confidence interval. Express the percentages in decimal form. ​

Answer 1

a. To construct a 90% confidence interval, we can use the following formula:

CI = p ± z*sqrt((p*(1-p))/n)

where:
p = proportion of yellow peas = 154/(427+154) = 0.265
z = z-score for a 90% confidence level = 1.645 (from a standard normal distribution table)
n = sample size = 427+154 = 581

Substituting the values, we get:

CI = 0.265 ± 1.645*sqrt((0.265*(1-0.265))/581)
CI = 0.265 ± 0.042
CI = (0.223, 0.307)

Therefore, we can say with 90% confidence that the true proportion of yellow peas in the population lies between 0.223 and 0.307.

b. The expected proportion of yellow peas is 0.25. Since the confidence interval does not contain 0.25, the results of the experiment appear to contradict the expectation that 25% of the offspring peas would be yellow.