Number of results: 21
Assume that the math SAT scores are normally distributed with a mean of 500 and a standard deviation of 100. If you score 560 on this exam, what percentage of those taking the test scored below you? semperfi
March 12, 2015 by bryan
A test is composed of six multiple choice questions where each question has 4 choices. If the answer choices for each question are equally likely, find the probability of answering more than 4 questions correctly.
October 20, 2010 by Anonymous
a set of integers consists of 2,3,5,7,11,12,x. if x is increased by 1 the median of the set stays unchanged. however, if x decreases by 1, the median of the set also decreases by 1. what is the value of x?
September 16, 2013 by busi
A student claims that if the odds in favor of winning a game are a:b, then out of every a+b games she would win a games. Hence, the probability of the event of winning the game is a/b+b Is the student's reasoning correct? why or why not?
February 20, 2015 by joe
I am doing a paper on the maritime ringlet butterfly. I've been through quite a bit of sites but I can't seem to get a hold of satistics on the estimation of how many maritime ringlet butterflies remain, or even any sort of stats at all. I also can't seem to understand what ...
September 10, 2008 by garrick
Assume that the mean hourly cost to operate a commercial airplane follows the normal distribution with a mean of $2,175 per hour and a standard deviation of $175. What is the operating cost for the lowest 10 percent of the airplanes? (Round z value to 2 decimal places. Omit ...
October 7, 2014 by Meredith
The average time a student spends studying just prior to a test is 36 minutes with a standard deviation of 5 minutes. This distribution approximates a normal curve. Find the percent of students who study just prior to the test for. a) more than 40 minutes b) between 35 and 45 ...
November 18, 2010 by badel
Probability and Satistics
Random Variables X and Y follow a joint distribution: f(x,y)=(6-x-y)/8 if 0<x<2, 2<y<4 and 0, else Find P(1<Y<3|X=1) I first got the marginal distribution for x and got (3-x)/4 (Integrated from 2 to 4)and then got the conditional dist and got (5-y)/4 and then...
November 2, 2013 by Katy
5. Give the standard deviation for the mean and median column. Compare these and be sure to identify which has the least variability? Standard deviation of Mean = 0.476169 Standard deviation of Median = 0.753937
October 5, 2011 by Hope
assume the probability that an electronic device will have a type 1 defect is 1% and the probability that it will have a type 2 defect is 2%. given that these two defects are not independent ,what is the probability that an item randomly selected has both a type 1 and type 2 ...
February 27, 2013 by natalie
A company that produces detergents wants to estimate the mean amount of detergent in 64-ounce jugs at a 99% confidence level. The company knows that the standard deviation of the amounts of detergent in all such jugs is .20 ounce. How large a sample should the company select ...
November 21, 2013 by ----
**I don't want the answer, I want to know how to set the problem up and the formula that I need to use. I am online with a tutor right now, and they can't help me. :-( The average price of a gallon of unleaded regular gasoline was reported to be $2.34 in northern Kentucky (The...
February 12, 2012 by Shannon
Among a random sample of 500 college students, the mean number of hours worked per week at non-college related jobs is 14.6. This mean lies 0.4 standard deviations below the mean of the sampling distribution. If a second sample of 500 students is selected, what is the ...
September 15, 2015 by Lissa
Test the following function to determine whether it is a probability function. If it is not, then make it into a probability function. (Give your answers correct to one decimal place.) R(x) = 0.2, for x = 0, 1, 2, 3, 4 (a) List the distribution of probabilities. R(0) =0 ...
September 21, 2014 by Vickie Huff
Monthly incomes of employees at a particular company have a mean of $5954. The distribution of sample means for samples of size 70 is normal with a mean of $5954 and a standard deviation of $259. Suppose you take a sample of size 70 employees from the company and find that ...
September 15, 2015 by Suzan
Jody checked the temperature 12 times on Monday, and the last digit of the temperature was odd six times more than it was even. On Tuesday, she checked it 18 times and the last digit was odd eight times more than it was even. Determine which series is closer to the 50/50 ratio...
September 15, 2015 by Lissa
In North American, female adult heights are approximately normal with a mean of 65 inches and a standard deviation of 3.5 inches. a.) If one female is selected at Random, what is the probablility that shes has a height 70 inches or higher? b.) The heights of 50 females were ...
November 14, 2010 by Benjamin
3.Give the mean for the mean column of the Worksheet. Is this estimate centered about the parameter of interest (the parameter of interest is the answer for the mean in question 2)? Mean 3.50 Standard deviation 1.317 4.Give the mean for the median column of the Worksheet. Is ...
December 4, 2011 by charlene