Maths Olympiad Prep

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Number theory Difficulty 1.9 Junior Find the answer

What is the correct ordering of the three numbers, 10810^8, 5125^{12}, and 2242^{24}?
(A) 224<108<512(B) 224<512<108(C) 512<224<108(D) 108<512<224(E) 108<224<512\textbf{(A)}\ 2^{24}<10^8<5^{12}\\ \textbf{(B)}\ 2^{24}<5^{12}<10^8 \\ \textbf{(C)}\ 5^{12}<2^{24}<10^8 \\ \textbf{(D)}\ 10^8<5^{12}<2^{24} \\ \textbf{(E)}\ 10^8<2^{24}<5^{12}

Multiple choice: answer with the letter of the option you want.

Solution

Use brute force.
108=100,000,00010^8=100,000,000,
512=244,140,6255^{12}=244,140,625, and
224=16,777,2162^{24}=16,777,216.
Therefore, (A)224<108<512\boxed{\text{(A)}2^{24}<10^8<5^{12}} is the answer. (Not recommended for the contest and will take forever)

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.