Question 1161483
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From combined age of 137 years first subtract 70 years and then subtract 31 year.


Then divide the result by 3 to get Jim's age as 12 years.


Then the father's age is 12 + 31 = 43  and the grandfather's age is 12 + 70 = 82 years.


<U>CHECK</U>.  12 + 43 + 82 = 137.    ! Correct !
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Solved.