Normal Distributions: purchase amounts by customers
Not what you're looking for?
Suppose it is known that the distribution purchase amounts by customers entering a popular retail store is approximately normal with mean $25 and standard deviation $8.
a. What is the probability that a randomly selected customer spends less than $35 at the store?
b. What is the probability that a randomly selected customer spends between $15 and $35 at the store?
c. What is the probability that a randomly selected customer spends more than $10 at the store?
d. Find the dollar amount such that 75% of all customers spend no more than this amount.
e. Find the dollar amount such that 80% of all customers spend at least this amount.
f. Find two dollar amounts, equidistant from the mean of $25, such that 90% of all customers are between these values.
Purchase this Solution
Solution Summary
The solution calculates probabilities using normal distribution.
Solution Preview
Please see attached file.
Suppose it is know that the distribution purchase amounts by customers entering a popular retail store is approximately normal with mean $25 and standard deviation $8.
a. What is the probability that a randomly selected customer spends less than $35 at the store?
Mean=M= $25
Standard deviation =s= $8
x= $35
z=(x-M)/s= 1.25 =(35-25)/8
Cumulative Probability corresponding to z= 1.25 is= 0.8944
Or Probability corresponding to x< 35.00 is Prob(Z)= 0.8944 0r= 89.44%
Answer: 0.8944 0r 89.44%
b. What is the probability that a randomly selected customer spends between $15 and $35 at the store?
Mean=M= $25
Standard deviation ...
Purchase this Solution
Free BrainMass Quizzes
Terms and Definitions for Statistics
This quiz covers basic terms and definitions of statistics.
Measures of Central Tendency
This quiz evaluates the students understanding of the measures of central tendency seen in statistics. This quiz is specifically designed to incorporate the measures of central tendency as they relate to psychological research.
Measures of Central Tendency
Tests knowledge of the three main measures of central tendency, including some simple calculation questions.
Know Your Statistical Concepts
Each question is a choice-summary multiple choice question that presents you with a statistical concept and then 4 numbered statements. You must decide which (if any) of the numbered statements is/are true as they relate to the statistical concept.