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
