Question 98991
In 3 hours Ben has walked an extra 0.9 x 3 = 2.7 miles. Subtracting the extra distance Ben walked gives a distance of 10.8 miles. They each walked half of that distance which is 5.4 miles. Alan is therefore walking at a rate of 1.8 miles per hour. Ben is walking 0.9 miles per hour faster ie 2.7 miles per hour.

Check Alan 3 x 1.8 = 5.4 miles
Ben 3 x 2.7 = 8.1 miles
Total distance covered = 5.4 + 8.1 = 13.5 miles