An algebra placement test was used to determine placement in mathematics courses. a sample of calculus students gave 50 scores. it is known stack sum space space with i equals 1 below and 50 on top x subscript i superscript 2 equals 20500 comma space sum from i equals 1 to 50 of space x subscript i equals 821. space use the sample standard deviation as the population deviation. if you want mu to be captured in a 96% confidence interval with length equal to 4, what is the minimum sample size?

Isuck at math ; ^; m a student solved this problem and said the answer is 3 feet. chase had a roll of ribbon that contained 7 7/8  feet of ribbon. he cut off one piece that was 3 5/8  feet long and another piece that was 1 1/4  feet from the roll. how much ribbon was left on the roll? is the student's answer reasonable? yes, the answer is reasonable. no, the answer is not reasonable. it should be about 2 feet. no, the answer is not reasonable. it should be about 13 feet. no, the answer is not reasonable. it should be about 4 feet.

Offering 30 if a plus b plus c equals 68 and ab plus bc plus ca equals 1121, where a, b, and c are all prime numbers, find the value of abc. the answer is 1978 but i need an explanation on how to get that.

Someone me! if you’re smart you can solve this!