The population standard deviation for the age of Foothill College students is 15 years. If we want to be 95% confident that the sample mean age is within 2 years of the true population mean age of Foothill College students , how many randomly selected Foothill College students must be surveyed?
From the problem, we know that σ = 15 and EBM = 2
z = z.025 = 1.96, becuase the confidence level is 95%.
n=\frac{z^{^{2}}\sigma ^{2}}{EBM^{2}}=\frac{1.96^{^{2}}15 ^{2}}{2^{2}}=216.09
using the sample size equation.
Use n = 217: Always round the answer UP to the next higher integer to ensure that the sample size is large enough.
Therefore, 217 Foothill College students should be surveyed in order to be 95% confident that we are within 2 years of the true population mean age of Foothill College students.

The table shows the demand and supply schedules for magazines. complete the following sentences. the equilibrium price of a magazine is $ 4 and the equilibrium quantity is 150 magazines a week. price (dollars per magazine) quantity demanded quantity supplied (magazines per week) 3.00 160 138 3.50 155 144 4.00 150 150 4.50 145 156 5.00 140 161 now a fall in the price of a newspaper decreases the quantity demanded by 11 magazines a week at each price. at the original equilibrium price, a occurs. to return to equilibrium, the price of a magazine a. surplus; rises b. shortage; rises c. shortage; falls d. surplus; falls as the market returns to equilibrium, the quantity demanded and the quantity supplied a. decreases; increases b. decreases; decreases c. increases; decreases d. increases; increases the new equilibrium price is $ nothing a magazine.

If his parents cannot alex with college, and two of his scholarships will be awarded to other students if he does not accept them immediately, which is the best option for him?

The monthly sales for yazici​ batteries, inc., were as​ follows: month jan feb mar apr may jun jul aug sept oct nov dec sales 19 20 17 12 11 18 16 17 19 22 21 24 this exercise contains only parts b and c. ​b) the forecast for the next month​ (jan) using the naive method​ = nothing sales ​(round your response to a whole​ number). the forecast for the next period​ (jan) using a​ 3-month moving average approach​ = nothing sales ​(round your response to two decimal​ places). the forecast for the next period​ (jan) using a​ 6-month weighted average with weights of 0.10​, 0.10​, 0.10​, 0.20​, 0.20​, and 0.30​, where the heaviest weights are applied to the most recent month​ = nothing sales ​(round your response to one decimal​ place). using exponential smoothing with alpha ​= 0.40 and a september forecast of 21.00​, the forecast for the next period​ (jan) = nothing sales ​(round your response to two decimal​ places). using a method of trend​ projection, the forecast for the next month​ (jan) = nothing sales ​(round your response to two decimal​ places). ​c) the method that can be used for making a forecast for the month of march is ▾ a 3-month moving average a 6-month weighted moving average exponential smoothing the naive method a trend projection .