SOLUTION: A man travels regularly between two cities . He takes 14/3hours , if he travels at his usual speed . He finds that if he increases his speed by 3km/h , he can reduce the

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Question 129781: A man travels regularly between two cities . He takes 14/3hours , if he travels at his usual speed . He finds that if he increases his speed by 3km/h , he can reduce the time by 1/3 hour . What is his usual speed ?
Pls help
Found 3 solutions by oscargut, josmiceli, test101:
Answer by oscargut(2103)   (Show Source):
You can put this solution on YOUR website!
let x the usual speed
then (14/3)x=(14/3-1/3)(x+3)
then (14/3)x=(13/3)x+13
then (1/3)x=13 then x=39
R: x= 39 km/h

Answer by josmiceli(19441)   (Show Source):
You can put this solution on YOUR website!
Let be his usual speed

Set the 's equal to eachother

multiply each side by

His usual speed is 39 km/hr
check answer:

OK

Answer by test101(1)   (Show Source):
You can put this solution on YOUR website!
let usual speed = x
So, 14/3x----------1
(14/3-1/3)(x+3)----2
14/3x=(13/30x+3
1/3x=13
x=13X3(by cross-multiplication)
x=39 Km/h