Mathematical and Physical Journal
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Problem C. 1132. (September 2012)

C. 1132. Which of the fractions


A=\frac{\overbrace{333\ldots 33}^{2012\text{ pieces}}\!1}{\underbrace{333\ldots
33}_{2012\text{ pieces}}\!4} \qquad
\text{and} \qquad B=\frac{\overbrace{222\ldots 22}^{2012\text{
pieces}}\!1}{\underbrace{222\ldots 22}_{2012\text{ pieces}}\!3}

is greater?

(5 pont)

Deadline expired on October 10, 2012.


Sorry, the solution is available only in Hungarian. Google translation

Megoldás.

A=1-\frac{3}{\underbrace{333\ldots 33}_{2012\text{ db}}\!4}
,\qquad B=1-\frac{2}{\underbrace{222\ldots 22}_{2012\text{
db}}\!3}.

Mivel

3\cdot{\underbrace{222\ldots 22}_{2012\text{ db}}\!3}=
{\underbrace{666\ldots 66}_{2012\text{
db}}\!9}>{\underbrace{666\ldots 66}_{2012\text{
db}}\!8}=2\cdot{\underbrace{333\ldots 33}_{2012\text{ db}}\!4},

ezért

\frac{3}{\underbrace{333\ldots 33}_{2012\text{ db}}\!4}>\frac{2}{\underbrace{222\ldots 22}_{2012\text{
db}}\!3}.

Vagyis

A<B.


Statistics:

538 students sent a solution.
5 points:222 students.
4 points:193 students.
3 points:33 students.
2 points:15 students.
1 point:13 students.
0 point:50 students.
Unfair, not evaluated:12 solutionss.

Problems in Mathematics of KöMaL, September 2012