Question 256422
I am happy for the rice and duck families but 
one problem per submission. 
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a+b+c=495
b=2a
c=3b
substitute 2a for b in c=3b  c=3*2a 
substitute 2a for b in a+b+c=495
a+2a+3*2a =495
9a=495
a=55

a = 55,   b = 110,   c = 330