Solution:
Given the data below:
From the question, 25 years is devoted to eating and working. Also, the number of years working will exceed the number of years eating food by 19 year.
Let x represent the number of years devoted to eating food and y represent the number of years devoted to workings.
Thus,

Thus, we have

To solve the above simultaneous equations by substitution, we substitute equation 2 into equation 1.
Thus,
![\begin{gathered} x+(x+19)=25 \\ open\text{ parentheses,} \\ x+x+19=25 \\ \Rightarrow2x+19=25 \\ subtract\text{ 19 from both sides of the equation,} \\ 2x+19-19=25-19 \\ \Rightarrow2x=6 \\ divide\text{ both sides by the coefficient of x, which is 2} \\ (2x)/(2)=(6)/(2) \\ \Rightarrow x=3 \end{gathered}]()
Substitute the value of 3 for x into equation 2.
Thus,

Hence,
22 years will be spent on working and 3 years will be spent on eating food.