A large pile of coins consists of pennies, nickels, dimes, and quarters.
a. how many different collections of 30 coins can be cho- sen if there are at least 30 of each kind of coin?
Explanation:If the bank has only quarters and dimes, and its total amount of coins is 250, then be x the amount of quarters it has, it will have 250−x dimes. A quarter is worth 0.25$, a dime is worth 0.10$ and the 250 coins together are worth 39.25$.
