KöMaL - Középiskolai Matematikai és Fizikai Lapok
Sign In
Sign Up


Problem K. 478. (November 2015)

K. 478. Farmer Thomas wanted to buy 4 metres of chain that costs 210 forints (HUF, Hungarian currency) a metre. The shop assistant tried to talk him into buying all the 10 metres they have in stock, but Farmer Thomas insisted on buying 4 metres only. However, he noticed that the assistant, on purpose, made a mistake in measuring the 4 metres, and cut off a shorter piece. Therefore he decided to ask for the other piece instead, which the assistant had to sell him for the price of 6 metres in order to avoid being caught cheating. Had he not noticed the cheating, it would have cost Farmer Thomas 14/9 as much to buy a metre of chain as it actually cost with this clever manoeuvre. How many metres of chain did Thomas get?

(6 pont)

Deadline expired on 10 December 2015.


105 students sent a solution.
6 points:61 students.
5 points:7 students.
4 points:3 students.
3 points:2 students.
0 point:30 students.
Unfair, not evaluated:2 solutions.

Our web pages are supported by:   Ericsson   Cognex   Emberi Erőforrás Támogatáskezelő   Emberi Erőforrások Minisztériuma   Nemzeti Tehetség Program    
MTA Energiatudományi Kutatóközpont   MTA Wigner Fizikai Kutatóközpont     Nemzeti
Kulturális Alap   ELTE   Morgan Stanley