Difference between revisions of "2003 AMC 8 Problems/Problem 4"

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==Solution==
 
==Solution==
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===Solution 1===
 
If all the children were riding bicycles, there would be <math> 2 \times 7=14 </math> wheels. Each tricycle adds an extra wheel and <math> 19-14=5 </math> extra wheels are needed, so there are <math> \boxed{\mathrm{(C)}\ 5} </math> tricycles.
 
If all the children were riding bicycles, there would be <math> 2 \times 7=14 </math> wheels. Each tricycle adds an extra wheel and <math> 19-14=5 </math> extra wheels are needed, so there are <math> \boxed{\mathrm{(C)}\ 5} </math> tricycles.
  
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===Solution 2===
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Setting up an equation, we have <math>a+b=7</math> children and <math>3a+2b=19</math>. Solving for the variables, we get, <math>a=\boxed{\mathrm{(C)}\ 5} </math> tricycles.
  
Setting up an equation, we have <math>a+b=7</math> children and <math>3a+2b=19</math>. Solving for the variables, we get, <math>a=\boxed{\mathrm{(C)}\ 5} </math> tricycles.
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~AllezW
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==See Also==
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{{AMC8 box|year=2003|num-b=3|num-a=5}}
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{{MAA Notice}}

Latest revision as of 16:15, 14 February 2024

Problem

A group of children riding on bicycles and tricycles rode past Billy Bob's house. Billy Bob counted $7$ children and $19$ wheels. How many tricycles were there?

$\mathrm{(A)}\ 2 \qquad\mathrm{(B)}\ 4 \qquad\mathrm{(C)}\ 5 \qquad\mathrm{(D)}\ 6 \qquad\mathrm{(E)}\ 7$

Solution

Solution 1

If all the children were riding bicycles, there would be $2 \times 7=14$ wheels. Each tricycle adds an extra wheel and $19-14=5$ extra wheels are needed, so there are $\boxed{\mathrm{(C)}\ 5}$ tricycles.

Solution 2

Setting up an equation, we have $a+b=7$ children and $3a+2b=19$. Solving for the variables, we get, $a=\boxed{\mathrm{(C)}\ 5}$ tricycles.

~AllezW

See Also

2003 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
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 AJHSME/AMC 8 Problems and Solutions

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