Suppose that for a given computer salesperson, the probability distribution of x

Question

Suppose that for a given computer salesperson, the probability distribution of x = the number of systems sold in one month is given by the following table.

(a) Find the mean value of x (the mean number of systems sold).
mean =  

(b) Find the variance and standard deviation of x. (Round the answers to four decimal places.)

(c) What is the probability that the number of systems sold is within 1 standard deviation of its mean value?
P( < x < + ) =  

(d) What is the probability that the number of systems sold is more than 2 standard deviations from the mean?
P(x < 2 or x > + 2) =

x 1 2 3 4 5 6 7 8 p(x) 0.04 0.10 0.13 0.30 0.29 0.12 0.01 0.01

Explanation / Answer

(a and b)

(c) P(2.776 < x < 5.524) = 0.13 + 0.3 + 0.29 = 0.72

(d) P(x < 1.402 or x > 6.898) = 0.01 + 0.01 = 0.02

Mean = [x * P(x)] = 4.150 Variance = [x^2 * P(x)] - Mean^2 = 1.888 SD = Variance = 1.374

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.