The area of a desk top is 8 ¾ square feet. if the length is 3 ½ft., find the width

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Imogene invested $8,000 in a bank account that pays 8 percent simple interest at the end of each year. her friend invested the same amount in stocks where the growth of the investment is represented as 2,000 times the square root of 2 less than the time lapsed in years. if y1 and y2 represent the amount earned in dollars and t is the time lapsed in years, which system of equations correctly represents the situation?

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.