The null hypothesis (H0) is that 23% of offspring peas will be yellow, while the alternative hypothesis (H1) is that the proportion of yellow peas is not equal to 23%.
H0: p = 0.23
H1: p ≠ 0.23
The significance level is at α = 0.01.
There is a total of 588 peas (448 green peas and 140 yellow peas).
pyellow peas = 140/588 = 0.2381
zstatistic = (0.2381 - 0.23) / √[(0.23)*(0.77)/588] = 0.0081 / 0.017 ≈ 4.76
Based on the z-score table, the p-value is well below 0.01. Therefore, the null hypothesis is rejected. There is sufficient evidence that the proportion of yellow peas in the offspring is different from 23%.