2015 AMC 12A Problems/Problem 15

Revision as of 03:00, 5 February 2015 by Supremeeditor (talk | contribs) (Solution)

Problem

What is the minimum number of digits to the right of the decimal point needed to express the fraction $\frac{123456789}{2^{26}\cdot 5^4}$ as a decimal?

$\textbf{(A)}\ 4\qquad\textbf{(B)}\ 22\qquad\textbf{(C)}\ 26\qquad\textbf{(D)}}\ 30\qquad\textbf{(E)}\ 104$ (Error compiling LaTeX. ! Extra }, or forgotten $.)

Solution

The fraction is equivalent to $\frac{123456789 \cdot 5^{29}}{10^{30}}.$ The answer is clearly $\textbf{(E)}.$

See Also

2015 AMC 12A (ProblemsAnswer KeyResources)
Preceded by
Problem 14
Followed by
Problem 16
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All AMC 12 Problems and Solutions
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