____years will be spent on working and ___years will be spent on eating food
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In the graph, we can see the following:
We know that a person will devote 28 years working and eating from the word problem. Also, the number of years working will exceed the number of years eating by 20. Then, we have:
[tex]\begin{gathered} \text{Number of years working }+\text{Number of years eating }=28 \\ 24+4=28 \end{gathered}[/tex]Therefore, a person will be spent 24 years working and 4 years eating food.