1. Genetics of peas.
According to genetic theory, the blossom color in the second generation of a certain cross of sweet peas should be red or white in a 3:1 ratio. That is, each plant has probability 3/4 of having red blossoms, and the blossom colors of separate plants are independent.
(a) What is the probability that exactly 9 out of 12 of these plants have red blossoms?
(b) What is the mean number of red-blossomed plants when 120 plants of this type are grown from seeds?
(c) What is the probability of obtaining at least 80 red-blossomed plants when 120 plants are grown from seeds?
2. The weight of a dozen eggs.
The weight of the eggs produced by a certain breed of hen is Normally distributed with mean 65 grams (g) and standard deviation 5 g. If cartons of such eggs can be considered to be SRSs of size 12 from the population of all eggs, what is the probability that the weight of a carton falls between 755 and 830 g?