Consider the sports ratings model in Section 7.6. If you were going to give more recent games more weight, how might you determine whether the weight given to a game from k weeks ago should be, say,...

Consider the sports ratings model in Section 7.6. If you were going to give more recent games more weight, how might you determine whether the weight given to a game from k weeks ago should be, say, (0.95)^k
or (0.9)^k
?

Four items are for sale in the Dollar Value store. The product and sum of their prices is $7.11. What is the price of each item?