Now you need a number for the population standard deviation, This number is not known, so you do a pilot study of 35 students and find the standard deviation s for the sample is songs — use this number as a substitute for Using the sample size formula, you calculate the sample size you need is which you round up to students you always round up when calculating n.
When the shorter sides are 20 feet, there is 40 feet of fencing left for the longer side. Authored by: Jay Abramson, et al.
Figure 9 Example 5: Finding the Maximum Value of a Quadratic Function A backyard farmer wants to enclose a rectangular space for a new garden within her fenced backyard. Analysis of the Solution This problem also could be solved by graphing the quadratic function.
So you need to take a random sample of at least college students in order to have a margin of error in the number of stored songs of no more than To find what the maximum revenue is, we evaluate the revenue function. That is, if the unit price goes up, the demand for the item will usually decrease.
Suppose you want to estimate the average number of songs college students store on their portable devices.
Hence this chart can be expanded to other confidence percentages as well. Determine the y-value of the vertex.
Find a formula for the area enclosed by the fence if the sides of fencing perpendicular to the existing fence have length L. What dimensions should she make her garden to maximize the enclosed area?