Difference between revisions of "2014 UNM-PNM Statewide High School Mathematics Contest II Problems/Problem 1"

(Created page with "== Problem == Four siblings BRYAN, BARRY, SARAH and SHANA are having their names monogrammed on their towels. Different letters may cost different amounts to monogram. If it c...")
 
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how much does it cost to monogram SHANA?
 
how much does it cost to monogram SHANA?
  
== Solution ==
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== Solution==
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We set up the following equations:
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<math>b+r+y+a+n= 21</math>
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<math>b+a+2r+y= 25</math>
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<math>s+2a+r+h= 18</math>
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We are asked to find the price of "Shana", or <math>s+h+2a+n</math>. We notice that this expression has no <math>b</math> or <math>y</math>, so we subtract the first equation from the second to eliminate those variables:
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<math>r-n=4</math>
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simplfying gets
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<math>r=n+4</math>
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Which we substitute into the third equation
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<math>s+2a+n+4+h=18</math>.
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<math>s+2a+n+h=14</math>.
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This matches the expression we need to solve for, so we are done. <math>\boxed{14}</math>.
  
 
== See also ==
 
== See also ==

Revision as of 16:21, 24 July 2016

Problem

Four siblings BRYAN, BARRY, SARAH and SHANA are having their names monogrammed on their towels. Different letters may cost different amounts to monogram. If it costs $\textdollar{21}$ to monogram BRYAN, $\textdollar{25}$ to monogram BARRY and $\textdollar{18}$ to monogram SARAH, how much does it cost to monogram SHANA?

Solution

We set up the following equations:

$b+r+y+a+n= 21$

$b+a+2r+y= 25$

$s+2a+r+h= 18$

We are asked to find the price of "Shana", or $s+h+2a+n$. We notice that this expression has no $b$ or $y$, so we subtract the first equation from the second to eliminate those variables:

$r-n=4$

simplfying gets

$r=n+4$

Which we substitute into the third equation

$s+2a+n+4+h=18$. $s+2a+n+h=14$.

This matches the expression we need to solve for, so we are done. $\boxed{14}$.

See also

2014 UNM-PNM Contest II (ProblemsAnswer KeyResources)
Preceded by
First question
Followed by
Problem 2
1 2 3 4 5 6 7 8 9 10
All UNM-PNM Problems and Solutions
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