MHB Comparison between two numbers

anemone
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Compare the numbers $2^{2016}$ and $3^{201}7^{604}$.

I don't have the time yet to try it, but I can tell this is a very delicious problem so I decided to make it as a challenge here and hopefully I can crack it when I've the time and am able. I hope too that you'll agree with me that this is a superb challenging problem and I'm looking forward to see how our members are going to solve it. :o
 
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anemone said:
Compare the numbers $2^{2016}$ and $3^{201}7^{604}$.

I don't have the time yet to try it, but I can tell this is a very delicious problem so I decided to make it as a challenge here and hopefully I can crack it when I've the time and am able. I hope too that you'll agree with me that this is a superb challenging problem and I'm looking forward to see how our members are going to solve it. :o

we have $3 * 7^3 = 1029 > 2^{10}$
so $\frac {3 * 7^3}{2^{10}} = \frac{1029}{1024} = 1 + \frac{5}{1024} < 1 + \frac{1}{201}$
hence $ (\frac {3 * 7^3}{2^{10}})^{201} < (1 + \frac{1}{201})^{201} < e $ as $(1+\frac{1}{x})^x < e$
so $ (3 * 7 ^3)^{201} < e * 2^{2010}$
or $3^{201} * 7^{603} < 3 * 2^{2010}$
or $3^{201} * 7^{604} < 21 * 2^{2010} < 64 * 2^{2010}$
or $3^{201} * 7^{604} < 2^{2016}$
hence $2^{2016}$ is larger
 
Last edited:
kaliprasad said:
we have $3 * 7^3 = 1029 > 2^{10}$
so $\frac {3 * 7^3}{2^{10}} = \frac{1029}{1024} = 1 + \frac{5}{1024} < 1 + \frac{1}{201}$
hence $ (\frac {3 * 7^3}{2^{10}})^{201} < (1 + \frac{1}{201})^{201} < e $ as $(1+\frac{1}{x})^x < e$
so $ (3 * 7 ^3)^{201} < e * 2^{2010}$
or $3^{201} * 7^{603} < 3 * 2^{2010}$
or $3^{201} * 7^{604} < 21 * 2^{2010} < 64 * 2^{2010}$
or $3^{201} * 7^{604} < 2^{2016}$
hence $2^{2016}$ is larger

Very well done kaliprasad!(Cool)
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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