The ratio of pay for working hours is:
[tex]\frac{24\text{ dollars}}{1.5\text{ hours}}[/tex]Then the proportion to find how much do you make in 8 hours is:
[tex]\frac{24\text{ dollars}}{1.5\text{ hours}}=\frac{x}{8\text{ hours}}[/tex]And now we need to solve for x:
[tex]\begin{gathered} \frac{24\times8}{1.5}=x \\ x=\frac{192}{1.5} \\ x=128 \end{gathered}[/tex]Thus, you make $128 in 8 hours.
b. The ratio is the same, what changes is the proportion:
[tex]\frac{24\text{ dollars}}{1.5\text{ hours}}=\frac{x}{12\text{ hours}}[/tex]Now, solve for x:
[tex]\begin{gathered} \frac{24\times12}{1.5}=x \\ x=\frac{288}{1.5} \\ x=192 \end{gathered}[/tex]You make $192 in 12 hours.