There are 30 musicians in the carter school marching band. how many of them play brass instruments

If 24 people have the flu out of 360 people, how many would have the flu out of 900. choose many ways you could use proportion that david would use to solve this problem

Four congruent circular holes with a diameter of 2 in. were punches out of a piece of paper. what is the area of the paper that is left ? use 3.14 for pi

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.