The Central Limit Theorem for Sums · Exercise 34
Salaries for teachers in a particular elementary school district are normally distributed with a mean of $44,000 and a standard deviation of $6,500. We randomly survey ten teachers from that district.
(a) In words, X = ______________
(b) X ~ _____(_____,_____)
(c) In words, ΣX = _____________
(d) ΣX ~ _____(_____,_____)
(e) Find the probability that the teachers earn a total of over $400,000.
(f) Find the 90^th percentile for an individual teacher's salary.
(g) Find the 90^th percentile for the sum of ten teachers' salary.
(h) If we surveyed 70 teachers instead of ten, graphically, how would that change the distribution in part d?
(i) If each of the 70 teachers received a $3,000 raise, graphically, how would that change the distribution in part b?
OpenStax, Introductory Statistics 2e · §7.2 The Central Limit Theorem for Sums · Exercise 34
No hints for this one.
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