Difference between revisions of "1988 AJHSME Problems/Problem 6"

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(Solution 2)
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==Solution 2==
 
==Solution 2==
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We expand <math>\frac{(0.2)^3}{(0.02)^2}</math>, and get <math>\frac{(0.2)*(0.2)*(0.2)}{(0.02)(0.02)}</math>. The two <math>0.02</math>'s "cancel" out with the two <math>0.2</math>'s, leaving the fraction as: <math>(10)*(10)*(0.2)</math>. Using basic calculations, we compute this expression to get <math>20\Rightarrow \mathrm{(E)}</math>.
  
 
==See Also==
 
==See Also==

Revision as of 23:15, 8 July 2020

Problem

$\frac{(.2)^3}{(.02)^2} =$

$\text{(A)}\ .2 \qquad \text{(B)}\ 2 \qquad \text{(C)}\ 10 \qquad \text{(D)}\ 15 \qquad \text{(E)}\ 20$

Solution

Converting the decimals to fractions gives us $\frac{(.2)^3}{(.02)^2} =\frac{\left( \frac{1}{5}\right)^3}{\left(\frac{1}{50}\right)^2}=\frac{50^2}{5^3}=\frac{2500}{125}=20\Rightarrow \mathrm{(E)}$.

Solution 2

We expand $\frac{(0.2)^3}{(0.02)^2}$, and get $\frac{(0.2)*(0.2)*(0.2)}{(0.02)(0.02)}$. The two $0.02$'s "cancel" out with the two $0.2$'s, leaving the fraction as: $(10)*(10)*(0.2)$. Using basic calculations, we compute this expression to get $20\Rightarrow \mathrm{(E)}$.

See Also

1988 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 5
Followed by
Problem 7
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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