Question

If a man walks at a speed of 4 kmph, how long will it take him to walk 3 km?

Answer 1

IF A BOY WALKS AT A SPEED OF 4 KM/HR,HE REACHES HIS SCHOOL 10 MINUTES BEFORE THE SCHOOL TIME.IF HE WALKS 3 KM/HR HE REACHES THE SCHOOL 10 MINUTES LATE.FIND THE DISTANCE BETWEEN HIS HOUSE AND HIS SCHOOL.
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To-school DATA:
distance = x km ; rate = 4 kph ; time = x/4 hrs
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From school DATA:
distance = x km ; rate = 3 kph ; time = x/3 hrs
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Note the time difference is 25 minutes.
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Equation:
from time - to time = 25/60 hrs
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x/3 - x/4 = 25/60
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Multiply thru by 60 to get:
20x - 15x = 25
5x = 25
x = 5 km (distance from house to school)
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Cheers,
Stan H. 

Answer 2

If it takes 1 hour for info 4 km

then I hour = 60 min

Now 60÷4 =15

so it takes 15 mins for 1 km

then for 3 km

15×3=45

so it will take 45 mins to walk 3 km