Answer is 20 hours.
Given:
Jenny can make 8 lawns in 5 hours.
The objective is to calculate the time required for her to mow 12 lawns.
Consider the required time as t.
The rate of equation can be represented as,
[tex]\begin{gathered} r=\frac{12}{8} \\ r=4 \end{gathered}[/tex]Now, the time required can be calculated as,
[tex]\begin{gathered} r=\frac{t}{5} \\ 4=\frac{t}{5} \\ t=20\text{ hours} \end{gathered}[/tex]Hence, the time required for her to mow 12 lawns is 20 hours.
