Can you provide some assistance to the math problem for my 6th grader who is in middle school. Thanks

While getting a recipe for the Thanksgiving feast. The teacher was talking on the phone with a friend who lives four miles north of her. She saw a flash of lightning through the window: fifteen seconds later, she heard a clap of thunder. Ten seconds after that she heard the thunder over the phone. Where did the lightning strike in relation to the teacher's house. (There are two possible answers. Sound travels about 1/5 mile per second. Some people say it's not good to be on the phone in a thunderstorm).

I think the advice given in the problem is extra.

Thanks Frustrated Mom.

To make the answer unique, replace "She saw a flash of lightning through the window" by "She saw a flash of lightning through the eastern window". 15 seconds later, the sound had traveled 3 miles and reached her. 10 seconds after that the sound had traveled 5 miles and reached her friends house.