Difference between revisions of "2017 AMC 10B Problems/Problem 20"

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==Solution==
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We note that the only thing that affects the parity of the factor are the powers of 2. Since there are <math>10+5+2+1 = 18</math> factors of 2, and since only haveing a 0 power of 2 makes the factor odd, then the answer is <math>\boxed{\textbf{(B) } \frac 1{19}}</math>.
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==See Also==
 
==See Also==
 
{{AMC10 box|year=2017|ab=B|num-b=19|num-a=21}}
 
{{AMC10 box|year=2017|ab=B|num-b=19|num-a=21}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Revision as of 12:15, 16 February 2017

Problem

Placeholder

Solution

We note that the only thing that affects the parity of the factor are the powers of 2. Since there are $10+5+2+1 = 18$ factors of 2, and since only haveing a 0 power of 2 makes the factor odd, then the answer is $\boxed{\textbf{(B) } \frac 1{19}}$.

See Also

2017 AMC 10B (ProblemsAnswer KeyResources)
Preceded by
Problem 19
Followed by
Problem 21
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 10 Problems and Solutions

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