Answer:
It would take him 108 minutes to mow the lawn.
Step-by-step explanation:
We can do proportion.
[tex] \frac{5 \: lawns}{36 \: minutes} = \: \frac{15 \: lawns}{x} [/tex]
[tex]36 \times 15 = 540 \\ 5 \times x = 5x[/tex]
[tex] \frac{540}{5} = \frac{5x}{5} [/tex]
[tex]108 = x[/tex]
