Difference between revisions of "2013 AMC 10A Problems/Problem 5"

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<math> \textbf{(A)}\ 15\qquad\textbf{(B)}\ 20\qquad\textbf{(C)}\ 25\qquad\textbf{(D)}\ 30\qquad\textbf{(E)}\ 35 </math>
 
<math> \textbf{(A)}\ 15\qquad\textbf{(B)}\ 20\qquad\textbf{(C)}\ 25\qquad\textbf{(D)}\ 30\qquad\textbf{(E)}\ 35 </math>
  
==Solution==
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==Solution 1==
  
 
The total amount paid is <math>105 + 125 + 175 = 405</math>.  To get how much each should have paid, we do <math>405/3 = 135</math>.
 
The total amount paid is <math>105 + 125 + 175 = 405</math>.  To get how much each should have paid, we do <math>405/3 = 135</math>.
  
 
Thus, we know that Tom needs to give Sammy 30 dollars, and Dorothy 10 dollars.  This means that <math>t-d = 30 - 10 = \boxed{\textbf{(B) }20}</math>.
 
Thus, we know that Tom needs to give Sammy 30 dollars, and Dorothy 10 dollars.  This means that <math>t-d = 30 - 10 = \boxed{\textbf{(B) }20}</math>.
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==Solution 2==
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The difference in the money that Tommy paid and Dorothy paid is <math>20</math>.  In order for them both to have paid the same amount, Tommy must pay <math>20</math> more than Dorothy.  The answer is <math>\boxed{\mathbb{B}}</math>.
  
 
==See Also==
 
==See Also==

Revision as of 12:21, 27 January 2015

Problem

Tom, Dorothy, and Sammy went on a vacation and agreed to split the costs evenly. During their trip Tom paid $105, Dorothy paid $125, and Sammy paid $175. In order to share costs equally, Tom gave Sammy $t$ dollars, and Dorothy gave Sammy $d$ dollars. What is $t-d$?


$\textbf{(A)}\ 15\qquad\textbf{(B)}\ 20\qquad\textbf{(C)}\ 25\qquad\textbf{(D)}\ 30\qquad\textbf{(E)}\ 35$

Solution 1

The total amount paid is $105 + 125 + 175 = 405$. To get how much each should have paid, we do $405/3 = 135$.

Thus, we know that Tom needs to give Sammy 30 dollars, and Dorothy 10 dollars. This means that $t-d = 30 - 10 = \boxed{\textbf{(B) }20}$.

Solution 2

The difference in the money that Tommy paid and Dorothy paid is $20$. In order for them both to have paid the same amount, Tommy must pay $20$ more than Dorothy. The answer is $\boxed{\mathbb{B}}$.

See Also

2013 AMC 10A (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
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
2013 AMC 12A (ProblemsAnswer KeyResources)
Preceded by
Problem 4
Followed by
Problem 6
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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