Question

3. A car has to cover the distance 60 km. If half of the total
time it travels with speed 80 km/h and in rest half time its
speed becomes 40 km/h, the average speed of car will be
(a) 60 km/h (b) 80 km/h (C) 120 km/h (d) 180 km/h​

Answer 1

Answer:

you have to use the formula of average speed as total distance/total time

Answer 2

Average speed

$= \frac{total \: distance}{total \: time} \\ = \frac{(80 \times \frac{time}{2}) + 40 \times \frac{time}{2} } {total \: time} \\ = {40 + 20} \\ = 60$