Respuesta :

Answer:

It takes him  hours to mow the third lawn

Explanation:

We are given that Evan takes  hours to mow Mr. Gals lawn and  hours to mow Mrs. Lee's lawn

This means that:

Time taken to mow the two lawns =  hours

Now, we are given that the time taken to mow the three lawns is  hours

This means that:

Time taken to mow the third lawn =  hours

Hope this helps :)