Question

A car moves with a speed of 30km/h for half an hour,
25km/hour for 1 hour and 40km/h for 2 hours. Calculate the
average speed of the car.​

Answer 1

Answer:

Hello friend

here is your answer

$average \: speed \: = \frac{toat \: distance}{ total \: time}$

• for first travelled distance

speed = 30km/hr

time = 30 minutes or 0.5 hr

distance = speed × time

= 30 × 0.5

= 15 km

• for second travelled distance

speed = 25 km/hr

time = 1 hr

distance = speed × time

= 25 × 1

= 25 km

• for third travelled distance

speed = 40 km/hr

time = 2 hr

distance = speed × time

= 40 × 2

= 80 km

Now calculating the average speed

total distance = 15 + 25 + 80= 120 km

total time = 0.5 + 1 +2 = 3.5 hr

$a.v. \: speed \: = \frac{120}{3.5} \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 34.28$

_____________________________

hope it helps.

thank you.