A survey found that 23% of Americans watch fireworks on TV on the 4th of July. Find the mean , variance, and standard deviation of the number of people that watch firework on TV if a random sample of 750 American is selected.

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Astore sells two types of radios. one type sells $87 and the other for $119. if 25 were sold and the sales were $2495, how many of the $87 radios were sold a) 5 b) 20 c) 15 d)10

1.two more than the quotient of a number and 6 is equal to 7 use the c for the unknown number translate the sentence into an equation