Problema Solution
On Monday, Carlos drove to work in 35 minutes. On Tuesday, he averaged 9 miles per hour more and arrived 7 minutes faster. How far (in miles) does Carlos travel from home to work?
Answer provided by our tutors
let
t1 = 35 min = 35/60 hr = 7/12 hr the time spent of traveling on Monday
v1 = the avg. speed on Monday
v2 = the avg. speed on Tuesday
t2 = the time spent of traveling on Tuesday
On Tuesday, he averaged 9 miles per hour more and arrived 7 minutes faster
v2 = v1 + 9
t2 = 35 - 7 minutes
t2 = 28 min
t2 = 28/60 hours
t2 = 7/15 hours
since speed = distance/time => distance = time*speed
v1*t1 = v2*t2
v1*(7/12) = (v1 + 9)8(7/15)
by solving the equation we find
v1 = 36 mph
click here to see the step by step solution of the equation
the distance = speed*time = v1*t1 = 36*(7/12) = 21 miles
Carlos travels 21 miles from home to work.