SOLUTION: After driving 120 km, 3/4 of a trip is completed. How long is the trip?

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Question 967694: After driving 120 km, 3/4 of a trip is completed. How long is the trip?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
THE FIFTH-GRADER MENTAL MATH SOLUTION:
If 3 fourths (3/4) is 120 km,
then 1 fourth (1/4) is 120 km divided by 3, which is 40 km.
If 40 km is 1/4 of the trip,
then the entire trip is 4 times that:
4 times 40 km, which is 160 km.

THE FANCY EQUATION ALGEBRA WAY:
x= total trip distance in km.
%283%2F4%29x= 3/4 of the total trip distance.
So, %283%2F4%29x=120 is our equation.
Solving:
%283%2F4%29x=120
Dividing both sides by 3%2F4 , (which, as you know,
is the same as multiplying by the reciprocal fraction, 4%2F3 )
we get
%283%2F4%29x%2F%283%2F4%29=120%2F%283%2F4%29 <---> %284%2F3%29%283%2F4%29x=%284%2F3%29%2A120
x=4%2A120%2F3 --> x=4%2A40 -->highlight%28x=160%29