Question

An aeroplane flies around a square fi​

Answer 1

Case 1:
d = 100km
s = 400km/h

T1 = 100/400 = 1/4 = 0.25h -----(i)

Case 2:
d = 100km
s = 500km/h

T2 = 100/500 = 1/5 = 0.2h ------(ii)

Case 3:
d = 100km
s = 600km/h

T3 = 100/600 = 1/6 = 0.16h -----(iii)

Case 4:
d = 100km
s = 700km/h

T4 = 100/700 = 1/7 = 0.14h ------(iv)

Total distance travelled = 100*4 = 400KM
Total time taken = T1 + T2 + T3 + T4
= 0.25 + 0.20 + 0.16 + 0.14
= 0.75 h

$Speed_{avg} = \frac {total \: distance \: travelled}{total \: time \: taken} \\ \\ Speed_{avg} = \frac {400}{0.75} \\ \\ Speed_{avg} = 533.33km/h$