Question

A journey by car takes 48 minutes at 65 kilometre per hour. How fast must the car go to finish the journey in 40 minutes​

Answer 1

Time tajen by car to complete journey = 48 min

speed of car = 65 km/h

we know

speed=

$\frac{Distance}{time} \\ </p><p></p><p>65= \frac{D}{ \frac{48}{60} } \\ </p><p></p><p>D=65× \frac{48}{60} =52km \\ </p><p></p><p>∴ speed \: of \: car \: to \: cover \: this \: distance \: in \: 40 \: min \\ </p><p></p><p>speed= \frac{52}{ \frac{40}{60} } = \frac{52}{40} ×63=26×3 \\ </p><p></p><p>speed = 78 km/h</p><p></p><p>$