SOLUTION: Mindy and Nate commute to NYC, a distance of 20 km. Mindy and Nate leave work at the same time. Nate travels 20 km/h faster than mindy and arrives home 10 minutes earlier. How fast
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: Mindy and Nate commute to NYC, a distance of 20 km. Mindy and Nate leave work at the same time. Nate travels 20 km/h faster than mindy and arrives home 10 minutes earlier. How fast
Log On
Question 962971: Mindy and Nate commute to NYC, a distance of 20 km. Mindy and Nate leave work at the same time. Nate travels 20 km/h faster than mindy and arrives home 10 minutes earlier. How fast did Nate drive Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Mindy and Nate commute to NYC, a distance of 20 km. Mindy and Nate leave work at the same time. Nate travels 20 km/h faster than mindy and arrives home 10 minutes earlier. How fast did Nate drive
--------------
Nate DATA:
dist = 20 km ; rate = x ; time = d/r = 20/x hrs
-----
Mindy DATA:
dist = 20 km ; rate = x-20 ; rime = d/r = 20/(x-20)hrs
-------
Equation::
Nate's time = Mindy's time - (1/6)hr
------
20/x = 20/(x-20) - (1/6)
Divide thru by 20 to get:
1/x = 1/(x-20) -1/120
Multiply thru by 120x(x-20) to get
120(x-20) = 120x - x(x-20)
120x-2400 = 120x - x^2-20x
x^2 + 20x - 2400 = 0
x = 40 kph
------------
Cheers,
Stan H.
--------------
(