400
Marcellus is on his way to visit his great great great grandma in Canada. He has to drive 150 miles to get to her house. On the first day, he drives 40 miles. On the second day, he drives 25 miles. On the third day, he drives 55 miles. How far does Marcellus have to drive on the fourth day to get to his great great great grandma's house?
30 miles