~~~15 points~~~

maria is 12 1/2 years older than sal. the sum of their ages is 28 1/2. which of the following equations can used to find their ages?

a. 28 1/2 - n = n/12 1/2

b. 28 1/2 - n = + 12 1/2

c. 28 1/2 + n = n + 12 1/2 - 28 1/2

d. 28 1/2 + n = 1(n - 12 1/2)

An optical inspection system is used to distinguish among different part types. the probability of a correct classification of any part is 0.92. suppose that three parts are inspected and that the classifications are independent. let the random variable x denote the number of parts that are correctly classified. determine the probability mass function of x. round your answers to four decimal places (e.g. 98.7654). x f(x) 0 1 2 3