The amount of sales tax paid on a purchase is rounded to the nearest cent. Assume that the round-off error is uniformly distributed in the interval .5 to .5 cent.

a. Write the formula for the probability curve describing the round- off error.

b. Graph the probability curve describing the round- off error.

c. What is the probability that the round- off error exceeds .3 cent or is less than .3 cent?

d. What is the probability that the round- off error exceeds .1 cent or is less than .1 cent? e. Find the mean and the standard deviation of the round- off error.

f. Find the probability that the round- off error will be within one standard deviation of the mean.