MathDB

4

Part of 2007 Junior Balkan Team Selection Tests - Moldova

Problems(1)

average age of the participants in a mathematics competition

Source: 2007 Moldova JBMO TST p4

2/20/2021
The average age of the participants in a mathematics competition (gymnasts and high school students) increases by exactly one month if three high school age students 1818 years each are included in the competition or if three gymnasts aged 1212 years each are excluded from the competition. How many participants were initially in the contest?
AverageSumcombinatorics