Question 1021958
 Jason's grandfather is four times older than he is. The sum of Jason's age and his grandfather's age is 80. How old is Jason? 
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g = 4j
g + j = 80
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Substitute for "g" and solve for "j"::
4j+j = 80
5j = 80
jason = 16 yrs old
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Cheers,
Stan H.
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