Solution :
Equation for Malcom's family travels after t hours is d = 65 t
From the graph, equation for Theo's family travels after travels after t hours is


For Malcom's family, speed
= 65 miles per hour
For Theo's family, speed
= 50 miles per hour
Malcom's family traveled faster than Theo's family by
= (65-50) miles per hour
= 15 miles per hour