Statistic
posted by Betty .
The amount of time it takes to take your order at the local Whaters restaurant has a population mean m of 3.1 minutes and a standard deviation s of 0.40 minutes. If you select a random sample of 16 customers:
Q3a: What is the probability that the mean time spent per customer is at least 3 minutes?

Statistic 
MathMate
It is not mentioned that the distribution is normal. We will assume that it is, either by assumption, or by an approximation using the central limit theorem (which preferably applies to samples of 30+).
With the assumption, we can see that the variance is σ²/n=0.4²/16=0.01, hence σ=0.1.
Look up the Normal distribution table for 1tail probability of 1σ which gives the probability of 10.8413=0.1587 for less than μ1σ=3.10.1=3.0 minutes.
Can you take it from here? 
Statistic 
ronnie
No
Respond to this Question
Similar Questions

Statistics...help
An article claimed that the typical supermarket trip takes a mean of 22 minutes. suppose that in an effort to test this claim, you select a sample of 50 shoppers at a local supermarket. the mean shopping time for the sample of 50 shoppers … 
Stat help
An article claimed that the typical supermarket trip takes a mean of 22 minutes. suppose that in an effort to test this claim, you select a sample of 50 shoppers at a local supermarket. the mean shopping time for the sample of 50 shoppers … 
Stats
An article (N. Hellmich. "'Supermarket Guru' Has a Simple Mantra,” USA Today, June 19, 2002, p. 70) claimed that the typical super market trip takes a mean of 22 minutes. Suppose that in an effort to test this claim, you select a … 
Math
An article (N. Hellmich. "'Supermarket Guru' Has a Simple Mantra,” USA Today, June 19, 2002, p. 70) claimed that the typical super market trip takes a mean of 22 minutes. Suppose that in an effort to test this claim, you select a … 
statistics
1. A random sample of size 49 is taken from a large population, measuring the time it takes to complete a driver’s license examination. The sample mean was found to be 47 minutes, and the sample standard deviation 5.89 minutes. Construct … 
statistic
The amount of time a bank teller spends with each customer has a population mean of 3.10 minutes and standard deviation of 0.40 minute. If a random sample of 16 customers is selected, a) what assumption must be made in order to solve … 
statistics
A random sample of size 81 is taken from a large population, measuring the time it takes to complete a driver’s license examination. The sample mean was found to be 43 minutes, and the sample standard deviation 5.71 minutes. Construct … 
Statistics
a laptop manufacturer finds that the average time it takes an employee to load a laptop with software is 20 minutes with a standard deviation 8 minutes. suppose you take a random sample of 81 employees. the standard deviation of the … 
math 120
A recent poll of a random sample of 400 students at a public 4year college showed the average (mean) amount of time spent using email was 49 minutes per day with a standard deviation of 44 minutes. a. find a 95% confidence interval … 
Stats
The manager of Lone Star Restaurant believes that the average wait time of the Saturday evening meal is 30 minutes. To test this belief, the manager selects 50 customers at random and computes the average wait time to be 34 minutes. …