Can anyone help with the problems below? Please explain, if possible.
It takes 60 minutes to assemble a bike, and the standard deviation is 22 minutes. Numerous random samples consisting of 121 customers who purchased the bike are taken.
a) The standard deviation of the sample means should be about____.
b) This standard deviation has a name; it is the ____________. c) You just assembled your daughter’s new bike, and it took you 90 minutes. The percentage of people who can do it in less time than you is ______ .
30% of the assemblies made by a manufacturer are defective. If the manufacturer inspects 1,000 assemblies, what is the probability that more than 275 of them will be defective?
And finally this:
Three cards are to be drawn from a deck with the five of hearts missing.
a) What is the probability that all three cards will be clubs?
b) What is the probability that all three cards will be of the same suit?