Difference between revisions of "2009 AMC 10A Problems/Problem 8"

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== Problem 8 ==
 
== Problem 8 ==
Three Generations of the Wen family are going to the movies, two from each generation. The two members of the youngest generation receive a <math>50</math>% discount as children. The two members of the oldest generation receive a <math>25\%</math> discount as senior citizens. The two members of the middle generation receive no discount. Grandfather Wen, whose senior ticket costs <dollar/><math>6.00</math>, is paying for everyone. How many dollars must he pay?
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Three generations of the Wen family are going to the movies, two from each generation. The two members of the youngest generation receive a <math>50</math>% discount as children. The two members of the oldest generation receive a <math>25\%</math> discount as senior citizens. The two members of the middle generation receive no discount. Grandfather Wen, whose senior ticket costs <math>\$6.00</math>, is paying for everyone. How many dollars must he pay?
  
 
<math>
 
<math>
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== Solution ==
 
== Solution ==
  
A senior ticket costs <dollar/><math>6.00</math>, so a regular ticket costs <math>6 \cdot \frac{1}{\frac{3}{4}}\:=\:6\cdot\frac{4}{3}\:=\:8</math> dollars. Therefore children's tickets cost half that, or <dollar/><math>4.00</math>, so we have:
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A senior ticket costs <math>\$6.00</math>, so a regular ticket costs <math>6 \cdot \frac{1}{\frac{3}{4}}\:=\:6\cdot\frac{4}{3}\:=\:8</math> dollars. Therefore children's tickets cost half that, or <math>\$4.00</math>, so we have:
  
 
<math>2(6+8+4)\:=\:36</math>
 
<math>2(6+8+4)\:=\:36</math>
  
So Grandfather Wen pays <math>\$36</math>, or <math>B</math>.
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So Grandfather Wen pays <math>\$36</math>, or <math>\fbox{B}</math>.
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==Solution 2==
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Using average, we know that assuming the middle-aged people's ticket cost x dollars, <math>2\cdot(100\%x+75\%x+50\%x)</math>. We average this into 2*(75%x+75%x+75%x). We know that 75%x=6.00, which means <math>6\cdot6</math> is the answer, or 36. -RealityWrites
  
 
== See Also ==
 
== See Also ==

Latest revision as of 15:53, 28 July 2023

Problem 8

Three generations of the Wen family are going to the movies, two from each generation. The two members of the youngest generation receive a $50$% discount as children. The two members of the oldest generation receive a $25\%$ discount as senior citizens. The two members of the middle generation receive no discount. Grandfather Wen, whose senior ticket costs $$6.00$, is paying for everyone. How many dollars must he pay?

$\mathrm{(A)}\ 34 \qquad \mathrm{(B)}\ 36 \qquad \mathrm{(C)}\ 42 \qquad \mathrm{(D)}\ 46 \qquad \mathrm{(E)}\ 48$

Solution

A senior ticket costs $$6.00$, so a regular ticket costs $6 \cdot \frac{1}{\frac{3}{4}}\:=\:6\cdot\frac{4}{3}\:=\:8$ dollars. Therefore children's tickets cost half that, or $$4.00$, so we have:

$2(6+8+4)\:=\:36$

So Grandfather Wen pays $$36$, or $\fbox{B}$.

Solution 2

Using average, we know that assuming the middle-aged people's ticket cost x dollars, $2\cdot(100\%x+75\%x+50\%x)$. We average this into 2*(75%x+75%x+75%x). We know that 75%x=6.00, which means $6\cdot6$ is the answer, or 36. -RealityWrites

See Also

2009 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
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

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