2010 AMC 8 Problems/Problem 7
Problem
Using only pennies, nickels, dimes, and quarters, what is the smallest number of coins Freddie would need so he could pay any amount of money less than a dollar?
Solution
You need 2 dimes, 1 nickel, and 4 pennies for the first 25 cents. From 26 cents to 50 cents, you only need to add 1 quarter. From 51 cents to 75 cents, you also only need to add 1 quarter. The same for 76 cents to 99 cents. Notice that instead of 100, it is 99 We are left with 3 quarters, 1 nickel, 2 dimes, and 4 pennies. so the correct answer is 3+2+1+4=10
See Also
2010 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 6 |
Followed by Problem 8 | |
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All AJHSME/AMC 8 Problems and Solutions |
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