a babysitter charges 9 dollars each hour she works plus a travel allowance of 5 dollars for each job. write an equation that relates the number of hours. the babysitter worked at a job for which she charged 77 dollars. how many hours did she work?

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.