A software engineer wishes to estimate, to within 5 seconds, the mean time that a new application takes to start up, with 95% confidence.  Estimate the minimum size sample required if the standard deviation of start up times for similar software is 9 seconds.

Assume that the weight loss for the first month of a diet program varies between 5 pounds and 50 pounds, and is spread evenly over the range of possibilities, so that there is a uniform distribution.  What is the probability of the weight loss more than 35 pounds?

A survey of 1000 college seniors working towards an undergraduate degree was conducted. Each student was asked, “Are you planning or not planning to pursue a graduate degree?” Of the 1000 surveyed, 652 stated that they were planning to pursue a graduate degree. a) Construct and interpret a 96% confidence interval for the proportion of college seniors who are planning to pursue a graduate degree. b) Find the minimum sample size would be needed for a 90% confidence interval with the margin of error of 0.025

Find the area under the standard normal curve to the right of  z = – 1.78.

A recent study claimed that less than 15% of middle school students are overweight.  In a random sample of 160 middle school students, 18 were found to be overweight.  At

A doctor of a local hospital is interested in estimating the birth weight of infants.  How large a sample must she select if she desired to be 98% confident that her estimate is within 2 ounces of the true mean?  Assume that the standard deviation is 7 ounces based on earlier studies.

A doctor of a local hospital is interested in estimating the birth weight of infants.  How large a sample must she select if she desired to be 96% confident that her estimate is within 2.5 ounces of the true mean?  Assume that the standard deviation is 7 ounces based on earlier studies.

The gray rectangle in the figure above represents a region of uniform magnetic field directed out of the page. A square loop of wire of side is in the plane of the page and is pulled at constant speed v through the field. Which of the following could show the current in the loop as a function of the position of the right edge of the loop?

The figure shows three objects (X, Y and Z) that have charges , , and , respectively. The objects are held on a fixed axis positioned shown. The magnitude of the electrostatic force exerted by object Y on object Z is . What is the magnitude of the net electrostatic force exerted on object Y due to the other two objects? On the left, X of charge negative 4q at position negative a, at center Y of charge positive q at position zero, and on the right Z of charge negative q at position a.

A beam of light with a wavelength of 500 nm falls normally on a diffraction grating. What is the spacing between slits on the grating if a first order maximum is observed at 30°?