Question

Moving at the rate of 70 km/hr, a car completes a journey in 18 mins. How long would it take to complete this journey,if the speed is increased to 84 km/he?

Answer 1

Answer:

15mins

Step-by-step explanation:

distance=speed*time

 =70*0.3=21km

time =x

speed=84

distance=21

time=distance/speed

 =21/84

=0.25 hrs or 15 mins

Answer 2

$distance=speed×time$

$distance=70× \frac{18}{60}$

$distance=70× \frac{3}{10}$

$distance=21 \:km$

so his distance is 21 km now time taken to reach in speed of 84 km/h

$time= \frac{distance}{speed}$

$time= \frac{21}{84}$

$time= \frac{1}{4}×60$

$(since \:time \:is \:in \:hour)$

$time \:taken = 15 \:minutes$