This preview shows page 1. Sign up to view the full content.
Unformatted text preview: v༇ Find the area under the standard normal curve between 2 and 2.
Soln: Using the empirical rule, P(Z<2) is about 95% Using software, P(Z<2) = 1P(Z>2)P(Z<2)
=12P(Z>2)=0.9545.
v༇ Find the area under the standard normal curve between z = 1.2 and z =1.6.
Soln: P(1.2<Z<1.6) = P(Z<1.6) P(Z<1.2)
= 0.9452 – 0.8849 = 0.0603. Another SAT problem
v༇ Want the proportion of scores below 680.
Not a neat use of 68, 95, 99.7 rule. µ = 505 and σ = 110. 680 To use a Normal table for this problem
680 − 505
= 1.59
① Find the zscore for 680: z =
110 ② 680 is 1.59 SD’s above the mean
③ Now need the proportion of values less than 1.59
for the standard normal distribution
ü༏ Use software to Zind P(Z<1.59) ü༏ Get 0.9441 ü༏ Answer: about 94.4% Another Illustrative Problem
The average amount of salt consumed per day by an American is 15 grams (the actual physiological minimum daily requirement for salt is only 220 milligrams). Sup...
View
Full
Document
This note was uploaded on 01/15/2014 for the course BUAD 310 taught by Professor Lv during the Fall '07 term at USC.
 Fall '07
 Lv

Click to edit the document details