Jake will earn $2400 if he sells his vintage watch set at a discount of 5% off the usual price. If he sells the watch set at a discount of 25% off the usual price, he will lose $900. What is the cost price of the vintage watch set?

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?