A bus covers a distance of 5 km in 20 min. If its speed is decreased by 3 km/hr, then find the time taken by the bus to cover the same distance.

Correct option is A

Given:

Distance = 5 km

Time = 20 min = $$\frac{20}{60}\text {hr}​ = \frac{1}{3}​$$ hr​

Speed reduction = 3 km/hr

Formula Used:

Speed =$$\frac{\text{Distance}}{\text{Time}}$$​​

New Time =$$\frac{\text{Distance}}{\text{New Speed}}$$​​

Solution:

Original Speed =$$\frac{5}{\frac{1}{3}} = 15$$ km /hr​

New Speed = Original Speed−3

New Speed = 15−3=12 km/hr

New Time =$$\frac{5}{12}​ \text hr = \frac{5}{12} \times$$​ 60 min = 25 min

Option  (A) is right.