Difference between revisions of "2017 AMC 12A Problems/Problem 1"

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==Solution==
 
==Solution==
  
By the greedy algorithm, we can take two 5-popsicle boxes and one 3-popsicle box with <math>\$8</math>. To prove that this is optimal, consider an upper bound as follows: at the rate of <math>\$3</math> per 5 popsicles, we can get <math>\frac{40}{3}</math> popsicles, which is less than 14. <math>\boxed{\textbf{D}}</math>.
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We can take two 5-popsicle boxes and one 3-popsicle box with <math>\$8</math>. Note that it is optimal since one popsicle is at the rate of <math>\$1</math> per popsicle, three popsicles at <math>\$\frac{2}{3}</math> per popsicle and finally, five popsicles at <math>\$\frac{3}{5}</math> per popsicle, hence we want as many <math>\$3</math> sets as possible. It is clear that the above is the optimal method. <math>\boxed{\textbf{D}}</math>.
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==Video Solution (HOW TO THINK CREATIVELY!!!)==
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https://youtu.be/VYo0SaDaMVs
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~Education, the Study of Everything
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==Video Solution==
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https://www.youtube.com/watch?v=Ro_koxVqd50
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~Math4All999
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==See Also==
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{{AMC10 box|year=2017|ab=A|num-b=1|num-a=3}}
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{{AMC12 box|year=2017|ab=A|before=First Problem|num-a=2}}
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{{MAA Notice}}

Latest revision as of 06:03, 14 September 2024

Problem

Pablo buys popsicles for his friends. The store sells single popsicles for $$1$ each, 3-popsicle boxes for $$2$, and 5-popsicle boxes for $$3$. What is the greatest number of popsicles that Pablo can buy with $$8$?

$\textbf{(A)}\ 8\qquad\textbf{(B)}\ 11\qquad\textbf{(C)}\ 12\qquad\textbf{(D)}\ 13\qquad\textbf{(E)}\ 15$

Solution

We can take two 5-popsicle boxes and one 3-popsicle box with $$8$. Note that it is optimal since one popsicle is at the rate of $$1$ per popsicle, three popsicles at $$\frac{2}{3}$ per popsicle and finally, five popsicles at $$\frac{3}{5}$ per popsicle, hence we want as many $$3$ sets as possible. It is clear that the above is the optimal method. $\boxed{\textbf{D}}$.

Video Solution (HOW TO THINK CREATIVELY!!!)

https://youtu.be/VYo0SaDaMVs

~Education, the Study of Everything

Video Solution

https://www.youtube.com/watch?v=Ro_koxVqd50

~Math4All999

See Also

2017 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 10 Problems and Solutions
2017 AMC 12A (ProblemsAnswer KeyResources)
Preceded by
First Problem
Followed by
Problem 2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AMC 12 Problems and Solutions

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