Two posts were offered to Mike. In one, the starting salary was $1200 and the annual increment was $80.

Question

In the second post, the salary commences at $80/month but with an annual increment of $120. Which post should Mike accept?

Answer 1

We should look at the 2 equations.

The first one is: y=1200+80x

The second one is: y=80+120x

We should see where they intersect using substitution, set the equations equal to each other:

1200+80x=80+120x Solve this by subtracting 80x from both sides

1200+80x-80x=80+120x-80x Simpligy

1200=80+40x Now subtract 80 from both sides

1200-80=80+40x-80 Simplify

1120=40x Divide both sides by 40

1120/40=40x/40

x= 28

What this means is that in 28 years, these salaries would be equal. So the answer is which job he should take is it depends. If he is going to work there for less than 28 years, he should take the higher starting salary. Otherwise, take the lower starting salary.