Juan makes a measurement in a chemistry laboratory and records the result in his lab report. the standard deviation of students' lab measurements is σ = 10 milligrams. juan repeats the measurement 3 times and records the mean x⎯⎯⎯ of his 3 measurements. (a) what is the standard deviation of juan's mean result? (that is, if juan kept on making 3 measurements and averaging them, what would be the standard deviation of all his x⎯⎯⎯′s? ) (b) how many times must juan repeat the measurement to reduce the standard deviation of x⎯⎯⎯ to 2.5? (a) 5.77 (b)

You are a clerk at convenience store. a customer owes 11.69 for a bag of potatoes chips. she gives you a five dollar bill. how much change should the customer receive?

Someone answer this asap rn for ! a discount store’s prices are 25% lower than department store prices. the function c(x) = 0.75x can be used to determine the cost c, in dollars, of an item, where x is the department store price, in dollars. if the item has not sold in one month, the discount store takes an additional 20% off the discounted price and an additional $5 off the total purchase. the function d(y) = 0.80y - 5 can be used to find d, the cost, in dollars, of an item that has not been sold for a month, where y is the discount store price, in dollars. create a function d(c(x)) that represents the final price of an item when a costumer buys an item that has been in the discount store for a month. d(c(x)) =

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 360, a standard deviation of 4, and a margin of error of 2.5%