Statistics
posted by cain .
An article in a Health Magazine suggested getting a dog to encourage more regular walking. A researcher for the article found that the distribution of time spent walking dogs is approximately normally distributed with a mean of 38 minutes per day. However he also found that 13% of dog owners walk their dogs less than 20 minutes per day. What is the standard deviation of the time, in minutes, dog owners walk their dog per day?
I don't know how to find standard deviation. I tried to use the z score formula to solve for SD but there are too many unknown variables. There must be some calculator function (because doing it by hand is hard and takes forever) but I don't know it. Please help, thanks!

you have the mean
go to the zscore table and find 0.1300
... this will tell you the number of standard deviations
divide the number into 20 min to find the SD
Respond to this Question
Similar Questions

Statistics
A recent article in a computer magazine suggested that the mean time to fully learn a new software program is 40 hours. A sample of 100 firsttime users of a new statistics program revealed the mean time to learn it was 39 hours with … 
statistics
Suppose that large dogs weights are normally distributed with a mean of 100 pounds and a standard deviation of 10 pounds. If one of these dogs is picked random: a) what is the probability that the dog will weigh over 110 pounds? 
statistics
a study of the time spent shopping in a supermarket for a market basket of 20 specific items showed an approximately uniform distribution between 20 minutes and 40 minutes. What is the probability that the shopping time will be a) … 
Math
Josh has a job walking dog.he walks a total of 18 dogs each week. Today,he is walking one third of the dogs.how many dogs is josh walking today? 
English
1. Walking on the street, I found a stray dog. 2. While I was walking on the street, I found a stray dog. 3. When I was walking on the street, I found a stray dog. 4. While I walked on the street, I found a stray dog. 5. When I walked … 
Math
Lesson: Division Rules 1/Charlie runs a dog walking service. He has 5 leashes. He uses 1 leash for each dog. How many dogs can charlie walk at the same time? 
statistics for health research
Descriptive statistics are widely used in qualitative research. When establishing if a population is normally distributed explain when the statistics of sample size, mean, mode, median, skewness and kurtosis will guide the researcher … 
2 STEP MATH EQUATIONS
eric has a dog walking business. He charges $13per dog he walks and $6 for the water he buys for the dogs. If he made $97 on Monday, write an equation to find the number of dogs he walked on Monday. I got an answer of 7 dogs on Monday. … 
math
Claire has a parttime job walking dogs Monday through Friday. Business has really increased. She is walking 3 more dogs per day than she did last week if she walked a total of 35 dogs this week, how many dogs did she walk per day … 
fractions
kado spent 1 2/3 hours painting a fence. Then he spent 4/5 of an hour walking the dog. How much longer did he spend painting than walking the dog