Every 10 years the alumni have a reunion. every 2 years the alumni have a soccer game. how often do the reunion and the game fall in the same year?

Assuming that they start the 10 and 2 years on the same year

one way is to find the least common multipule by listing factors and including all of them
10=2 times 5
2=2
we need to have at leas 1 2 and 1 5
the answer is 10
every 10 years is the answer
another way is to list them
exg they started at 2000
socker        reunion
2002            2000
2004
2006
2008
2010           2010

the answe ris every 10 years