## 139. Math Puzzle $12 / 76$

Ralf and Marion had set their watches, real "vintages," at the beginning of a longer hike. At the destination, Marion's watch shows 13:46 and Ralf's 14:13.

What time is it really, if Marion's watch gains 2 minutes daily and Ralf's old alarm clock loses 4 minutes daily?
The display difference of both clocks increases by 2 minutes daily, with ( $\approx 33$ percent of 6 minutes) or 4 minutes deviating from the displays.

In the present case, the difference is 27 minutes, with the actual time of Marion's fast-running clock deviating by 33 percent $\cdot 27$ minutes $=9$ minutes. Therefore, it is $13.46+0.09=$ 13.55.