Difference between revisions of "1985 AJHSME Problems/Problem 3"

(New page: ==Problem== <math>\frac{10^7}{5\times 10^4}=</math> <math>\text{(A)}\ .002 \qquad \text{(B)}\ .2 \qquad \text{(C)}\ 20 \qquad \text{(D)}\ 200 \qquad \text{(E)}\ 2000</math> ==Solution=...)
 
(Solution 2 (Brute Force))
 
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==Solution==
 
==Solution==
  
{{Solution}}
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We immediately see some canceling. We see powers of ten on the top and on the bottom of the fraction, and we make quick work of this: <cmath>\frac{10^7}{5 \times 10^4} = \frac{10^3}{5}</cmath>
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We know that <math>10^3 = 10 \times 10 \times 10</math>, so
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<cmath>\begin{align*}
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\frac{10^3}{5} &= \frac{10\times 10\times 10}{5} \\
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&= 2\times 10\times 10 \\
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&= 200 \\
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\end{align*}</cmath>
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So the answer is <math>\boxed{\text{D}}</math>
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== Solution 2 (Brute Force) ==
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<math>10^7</math> is <math>10000000</math>
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<math>5 \times 10^4</math> is <math>50000</math>
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Thus the answer is <math>200</math>, or <math>\boxed{\textbf{(D)}\ 200}</math>
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==Video Solution by BoundlessBrain!==
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https://youtu.be/BfFv227egOg
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==Video Solution==
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https://youtu.be/KW5HexBjEHU
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~savannahsolver
  
 
==See Also==
 
==See Also==
  
[[1985 AJHSME Problems]]
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{{AJHSME box|year=1985|num-b=2|num-a=4}}
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[[Category:Introductory Algebra Problems]]
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{{MAA Notice}}

Latest revision as of 21:07, 2 October 2024

Problem

$\frac{10^7}{5\times 10^4}=$


$\text{(A)}\ .002 \qquad \text{(B)}\ .2 \qquad \text{(C)}\ 20 \qquad \text{(D)}\ 200 \qquad \text{(E)}\ 2000$

Solution

We immediately see some canceling. We see powers of ten on the top and on the bottom of the fraction, and we make quick work of this: \[\frac{10^7}{5 \times 10^4} = \frac{10^3}{5}\]

We know that $10^3 = 10 \times 10 \times 10$, so

\begin{align*} \frac{10^3}{5} &= \frac{10\times 10\times 10}{5} \\ &= 2\times 10\times 10 \\ &= 200 \\ \end{align*}

So the answer is $\boxed{\text{D}}$

Solution 2 (Brute Force)

$10^7$ is $10000000$

$5 \times 10^4$ is $50000$

Thus the answer is $200$, or $\boxed{\textbf{(D)}\ 200}$

Video Solution by BoundlessBrain!

https://youtu.be/BfFv227egOg

Video Solution

https://youtu.be/KW5HexBjEHU

~savannahsolver

See Also

1985 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 2
Followed by
Problem 4
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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