Difference between revisions of "2004 AMC 12B Problems/Problem 1"

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== Problem ==
 
Jasmine had <math>2</math> paperclips on Monday, then she had <math>6</math> on Tuesday, and her number of paperclips proceeded to triple on each subsequent day. On what day of the week did she first have more than <math>100</math> paperclips?
 
Jasmine had <math>2</math> paperclips on Monday, then she had <math>6</math> on Tuesday, and her number of paperclips proceeded to triple on each subsequent day. On what day of the week did she first have more than <math>100</math> paperclips?
  
==Solution==
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== Solution ==
 
Each day Jenny makes half as many free throws as she does at the next practice. Hence on the fourth day she made <math>\frac{1}{2} \cdot 48 = 24</math> free throws, on the third <math>12</math>, on the second <math>6</math>, and on the first <math>3 \Rightarrow \mathrm{(A)}</math>.
 
Each day Jenny makes half as many free throws as she does at the next practice. Hence on the fourth day she made <math>\frac{1}{2} \cdot 48 = 24</math> free throws, on the third <math>12</math>, on the second <math>6</math>, and on the first <math>3 \Rightarrow \mathrm{(A)}</math>.
  
 
Because there are five days, or four transformations between days (day 1 <math>\rightarrow</math> day 2 <math>\rightarrow</math> day 3 <math>\rightarrow</math> day 4 <math>\rightarrow</math> day 5), she makes <math>48 \cdot \frac{1}{2^4} = \boxed{\mathrm{(A)}\ 3}</math>
 
Because there are five days, or four transformations between days (day 1 <math>\rightarrow</math> day 2 <math>\rightarrow</math> day 3 <math>\rightarrow</math> day 4 <math>\rightarrow</math> day 5), she makes <math>48 \cdot \frac{1}{2^4} = \boxed{\mathrm{(A)}\ 3}</math>
  
==See Also==
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== See Also ==
 
{{AMC12 box|year=2004|ab=B|before=First Question|num-a=2}}
 
{{AMC12 box|year=2004|ab=B|before=First Question|num-a=2}}
  
 
[[Category:Introductory Algebra Problems]]
 
[[Category:Introductory Algebra Problems]]
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 01:52, 7 January 2021

Problem

Jasmine had $2$ paperclips on Monday, then she had $6$ on Tuesday, and her number of paperclips proceeded to triple on each subsequent day. On what day of the week did she first have more than $100$ paperclips?

Solution

Each day Jenny makes half as many free throws as she does at the next practice. Hence on the fourth day she made $\frac{1}{2} \cdot 48 = 24$ free throws, on the third $12$, on the second $6$, and on the first $3 \Rightarrow \mathrm{(A)}$.

Because there are five days, or four transformations between days (day 1 $\rightarrow$ day 2 $\rightarrow$ day 3 $\rightarrow$ day 4 $\rightarrow$ day 5), she makes $48 \cdot \frac{1}{2^4} = \boxed{\mathrm{(A)}\ 3}$

See Also

2004 AMC 12B (ProblemsAnswer KeyResources)
Preceded by
First Question
Followed by
Problem 2
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 AMC 12 Problems and Solutions

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