Difference between revisions of "2022 AMC 8 Problems/Problem 7"

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==Solution==
 
==Solution==
  
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Notice that the amount of kilobits in this song is <math>4.2 \cdot 8000 = 8 \cdot 7 \cdot 6 \cdot 100.</math>
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We must divide this by <math>56</math> in order to find out how many seconds this song would take to download. <math>\frac{\cancel{8}\cdot\cancel{7}\cdot6\cdot100}{\cancel{56}} = 600.</math> Finally, we divide  this number by <math>60</math> because this is the number of <i>seconds</i>, not minutes in the song, to get an answer os <math>\boxed{\textbf{(B) } 10}</math>
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~wamofan
 
==See Also==  
 
==See Also==  
 
{{AMC8 box|year=2022|num-b=6|num-a=8}}
 
{{AMC8 box|year=2022|num-b=6|num-a=8}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 11:47, 28 January 2022

Problem

When the World Wide Web first became popular in the $1990$s, download speeds reached a maximum of about $56$ kilobits per second. Approximately how many minutes would the download of a $4.2$-megabyte song have taken at that speed? (Note that there are $8000$ kilobits in a megabyte.)

$\textbf{(A) } 0.6 \qquad \textbf{(B) } 10 \qquad \textbf{(C) } 1800 \qquad \textbf{(D) } 7200 \qquad \textbf{(E) } 36000$

Solution

Notice that the amount of kilobits in this song is $4.2 \cdot 8000 = 8 \cdot 7 \cdot 6 \cdot 100.$ We must divide this by $56$ in order to find out how many seconds this song would take to download. $\frac{\cancel{8}\cdot\cancel{7}\cdot6\cdot100}{\cancel{56}} = 600.$ Finally, we divide this number by $60$ because this is the number of seconds, not minutes in the song, to get an answer os $\boxed{\textbf{(B) } 10}$

~wamofan

See Also

2022 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 6
Followed by
Problem 8
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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