document.write( "Question 977126: Which of the following is the greatest?
\n" ); document.write( "a. \"3%5E210\"
\n" ); document.write( "b. \"7%5E140\"
\n" ); document.write( "c. \"17%5E105\"
\n" ); document.write( "d. \"31%5E84\"
\n" ); document.write( "Please give detailed solution.
\n" ); document.write( "(NOTE: Don't use logarithm. It has been removed from syllabus, and I have to make my students understand without using log)
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Algebra.Com's Answer #598662 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
Which of the following is the greatest?
\n" ); document.write( "a. \"3%5E210\"
\n" ); document.write( "b. \"7%5E140\"
\n" ); document.write( "c. \"17%5E105\"
\n" ); document.write( "d. \"31%5E84\"
\n" ); document.write( "---------------
\n" ); document.write( "3^210 = 9^105, obviously less than 17^105, so a is eliminated.
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\n" ); document.write( "Using a calculator:
\n" ); document.write( "7^140 = 2.059e118
\n" ); document.write( "17^105 = 1.57e129
\n" ); document.write( "31^84 = 1.88e125
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\n" ); document.write( "c wins again.
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\n" ); document.write( "You can change them all to the same base, eg, 7, but that would require either logs or a calculator.
\n" ); document.write( "----
\n" ); document.write( "eg,
\n" ); document.write( "7^140 = (2^2.8)^140 = 2^392
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\n" ); document.write( "ooooooooooooooh, John's answer is cool.
\n" ); document.write( "I might have figured that out eventually.
\n" ); document.write( "I should have spotted that 3, 7, 17 & 31 are all 2^n plus or minus 1.
\n" ); document.write( "In short, his solution is elegant.
\n" ); document.write( "Probably with assistance from Satan, since we all know god is stupid.
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