Question 101190
Let x=his age when he died (ie his life span)


{{{(1/4)x+(1/7)x+5+(1/2)x=x}}} Translate the following word problem



{{{7x+4x+140+14x=28x}}} Multiply both sides by the LCD 28 to make every number a whole number





{{{7x+4x+140+14x=28x}}} Start with the given equation



{{{25x+140=28x}}} Combine like terms on the left side



{{{25x=28x-140}}}Subtract 140 from both sides



{{{25x-28x=-140}}} Subtract 28x from both sides



{{{-3x=-140}}} Combine like terms on the left side



{{{x=(-140)/(-3)}}} Divide both sides by -3 to isolate x




{{{x=140 / 3}}} Reduce


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Answer:

So our answer is {{{x=140 / 3}}}  (which is {{{x=46.6666666666667}}} in decimal form)




So the father was about 47 when he died