In an economy with no taxes and no imports, when disposable income increases from $2000 to $3000, consumption increases from $1500 to $2100. given this information, the marginal propensity to consume is

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends > a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

Ashop owner uses a reorder point approach to restocking a certain raw material. lead time is six days. usage of the material during lead time is normally distributed with a mean of 42 pounds and a standard deviation of four pounds. when should the raw material be reordered if the acceptable risk of a stockout is 3 percent?

An allergy products superstore buys 6000 of their most popular model of air filters each year. the price of the air filters is $18. the cost of ordering and receiving shipments is $12 per order. accounting estimates annual carrying costs are 20% of the price. the supplier lead time is 2 days. the store operates 240 days per year. each order is received from the supplier in a single delivery. there are no quantity discounts. what is the store’s minimum total annual cost of placing orders & carrying inventory?