Question 318329
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Let *[tex \Large x] represent the grandson's age.  Then *[tex \Large 7x] is the father's age and *[tex \Large 12x] is the grandfather's age.


The sum:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ x\ +\ 7x\ +\ 12x\ =\ 100]


Solve for *[tex \Large x] then multiply by 12.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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