Will walking at a 4 mph speed 45 minutes a day help me lose weight?

i do a 45 minute "walk" aerobic workout everyday that is the equivalent of 3 miles. i want to shed 10 pounds so i'm doing this as well as weight watchers. 3 or 4 days a week i do a more intense aerobic workout in addition to the "walking" one. will this be enough to drop the weight?