Problema Solution
Ms. Fisher drove from here to Texas and then back on the same route. Going she averaged 70 mph and returning she averaged 60 mph. The total trip, there and back, took 35 hours. How far is it from here to Texas? Round your answer to the nearest mile.
Answer provided by our tutors
let
v1 = 70 mph the average speed to Texas
t1 = the time of the travel to Texas
v2 = 60 mph the average speed from Texas
t2 = the time of the travel from Texas
since average speed = distance/time = > distance = speed*time we have
v1*t1 = v2*t2
70*t1 = 60*t2
the total trip, there and back, took 35 hours
t1 + t2 = 35
by solving the system of equations
70*t1 = 60*t2
t1 + t2 = 35
we find
t1 = 210/13 hr
t2 = 245/23 hr
click here to see the step by step solution of the system of equations
the distance from here to Texas is v1*t1 = 70*210/13 = 1,131 miles.