Answer:
It takes him hours to mow the third lawn
Step-by-step 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 :)