Question

efore hosting their annual Chess Tournament and Spelling Bee, a school received 7 boxes of honorary medals: one medal for every participant. After the Chess Tournament, two boxes were empty and the rest were still closed. After the Spelling Bee, which had twice as many participants, there were 72 medals left. How many people competed in the Chess Tournament?

Answer 1

If 2 boxes were used to honor Chess tournament participants and 2*2 = 4 boxes were used to honor Spelling Bee participants, there remained 1 closed box at the end of competition. That box apparently had 72 medals in it.

The number of Chess Tournament participants was 2*72 = 144.