Q20 of 35 Page 55

A person goes to his office from his home daily at a fixed speed. But today he decided to reduce his speed by 20%. As a result he reaches his office 16 minutes late. What's the actual time he takes to reach his office daily?

Let v be the fixed speed of the person and t be the actual time taken to reach office.

Now, Distance to Office = Speed × Time = vt


Now, the speed is decreased by 20%


So, New Speed = v – 0.2 × v


= v =


And hence the new time taken is given by:


New Time Taken = t + 16


So, distance to office = × (t + 16)


Now, we know that distance to office is always fixed.


So, × (t + 16) = vt


= t


4t + 64 = 5t


t = 64 s


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