9. In gym class, students were asked to form six equal groups. If there were 15 students in EACH GROUP, then how many TOTAL students were there

Acoin bank containing only dimes and quarters has 12 more dimes than quarters. the total value of the coins is $11. how many quarters and dimes are in the coin bank?

Alistair has 5 half-pounds chocalate bars. it takes 1 1/2 pounds of chocalate,broken into chunks, to make a batch of cookies. how many batches can alistair mke with chocalate he has on his hand?

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.