# Difference between revisions of "1981 AHSME Problems/Problem 16"

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+ | ==Solution (Faster Way)== | ||

+ | Every 2 numbers in base 3 represents 1 number in base 9. | ||

+ | The first 2 numbers on the left,12 = 1(3) + 2(1) = 5. | ||

+ | |||

+ | So the answer is <math> \textbf{(E)}\ 5.</math> |

## Latest revision as of 20:56, 5 May 2021

## Problem

The base three representation of is The first digit (on the left) of the base nine representation of is

## Solution (Long Way)

Convert to base 10 then convert the result to base 9.

Therefore, the answer is

-edited by coolmath34

## Solution (Faster Way)

Every 2 numbers in base 3 represents 1 number in base 9. The first 2 numbers on the left,12 = 1(3) + 2(1) = 5.

So the answer is