Difference between revisions of "2021 JMPSC Sprint Problems/Problem 2"

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-OofPirate
 
-OofPirate
  
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== Solution 2 ==
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You want as many quarters in order to cut down on the number of coins. The most amount of quarters you can have is <math>11</math>. Since you can't use three cents on anything other than pennies, the remaining coins are <math>3</math> pennies. Therefore <math>11+3=14</math>
  
 
==See also==
 
==See also==

Revision as of 10:09, 12 July 2021

Problem

Brady has an unlimited supply of quarters ($0.25), dimes ($0.10), nickels ($0.05), and pennies ($0.01). What is the least number (quantity, not type) of coins Brady can use to pay off $$2.78$?

Solution

It is generally best to use the smallest number of coins with the most value, specifically the quarters, for taking away a big chunk of the problem. We are able to fit $11$ quarters, or $$2.75$ into $$2.78$. That only leaves $3$ cents. We cannot put any nickels nor dimes, therefore we require three pennies to get a total of $$2.78$.

The least number of coins Brady can use to pay off $$2.78$ will be $14$ coins.

-OofPirate

Solution 2

You want as many quarters in order to cut down on the number of coins. The most amount of quarters you can have is $11$. Since you can't use three cents on anything other than pennies, the remaining coins are $3$ pennies. Therefore $11+3=14$

See also

  1. Other 2021 JMPSC Sprint Problems
  2. 2021 JMPSC Sprint Answer Key
  3. All JMPSC Problems and Solutions

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