The mean value of land and buildings per acre from a sample of farms is $1400, w

Question

The mean value of land and buildings per acre from a sample of farms is $1400, with a standard deviation of $200. The data set has a bell-shaped distribution. Assume the number of farms in the sample is 77 (a) Use the empirical rule to estimate the number of farms whose land and building values per acre are between $1000 and $1800 farms (Round to the nearest whole number as needed) (b) If 20 additional farms were sampled, about how many of these additional farms would you expect to have land and building values between $1000 per acre and $1800 per acre? farms out of 20 (Round to the nearest whole number as needed )

Explanation / Answer

Solution:- mean = 1400,sd = 200
a)Emprical rule hols only normal populations.
P(1000 < X < 1800) = P((1000-1400)/200) < Z < (1800-1400)/200)
= P(-2 < Z < 2)
= 0.9544
Multiply this percentage by the sample size 77
=> 77*0.9544 = 73.4888 = 74(frames)

b) 20*0.9544 = 19.088 = 19(frames)

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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