Question

an aeroplane covers 2500 km,1200 km,and 500 km at the rate of 500 km/hr ,400 km/hr and 250 km/he respectively. find it's average speed for the whole journey.​

Answer 1

Answer:

D¹ = 2500km

S¹ = 500 km/hr

T¹ = $\frac{D¹}{S¹}$

T¹ = $\frac{2500}{500}$ = 5hrs

D² = 1200km

S² = 400km/hr

T² = $\frac{D²}{S²}$

T² = $\frac{1200}{400}$ = 3hrs

D³ = 500

S³ = 250

T³ = $\frac{D³}{S³}$

T³ = $\frac{500}{250}$ = 2hrs

Average speed = Total distance / total time

Total distance = 2500+1200+500km

= 4,200km

Total time. = 5+3+2

= 10hrs

Average speed = 4,200km/10hrs

420km/hr