We have given two sets, the intersection of M and N is the set that contains elements that belong to M and to N at the same time. In simple words M ∩ N means common elements in both M and N.
In the given question one set is empty set. Since the empty set is included in any set, it is also included in N although we don't see it. Therefore the common element in both the sets is empty set
First, you do 1/4 • 9 to find the total amount that is in the bag, which is 2 1/4 cups. Then, you do 2 1/4 - 5/8 to find out how much is left in the bag. There is 1 5/8 cups of trail mix left in the bag.