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

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== Problem ==
 
== Problem ==
  
Brady has an unlimited supply of quarters (<math>0.25), dimes (</math>0.10), nickels (<math>0.05), and pennies (</math>0.01). What is the least number (quantity, not type) of coins Brady can use to pay off <math>\$2.78</math>?
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Brady has an unlimited supply of quarters (<math>\$0.25</math>), dimes (<math>\$0.10</math>), nickels (<math>\$0.05</math>), and pennies (<math>\$0.01</math>). What is the least number (quantity, not type) of coins Brady can use to pay off <math>\$2.78</math>?
  
 
== Solution ==
 
== Solution ==
  
 
To minimize the number of coins, we need to maximize the amount of high-valued coins we use. 11 quarters are worth <math>\$2.75</math>, which is the most quarters we can use to get a value less than or equal to <math>\$2.78</math>. Finally, we can add 3 pennies to get a total of <math>\$2.87</math>, so the answer is <math>11+3=14</math>.
 
To minimize the number of coins, we need to maximize the amount of high-valued coins we use. 11 quarters are worth <math>\$2.75</math>, which is the most quarters we can use to get a value less than or equal to <math>\$2.78</math>. Finally, we can add 3 pennies to get a total of <math>\$2.87</math>, so the answer is <math>11+3=14</math>.

Latest revision as of 18:30, 10 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

To minimize the number of coins, we need to maximize the amount of high-valued coins we use. 11 quarters are worth $$2.75$, which is the most quarters we can use to get a value less than or equal to $$2.78$. Finally, we can add 3 pennies to get a total of $$2.87$, so the answer is $11+3=14$.