Question

145
129. If a car covers 90 km in 2 & 1/2 hrs., time
required to cover 30 km with the same speed will be
(a) 50 mins.
(b) 45 mins.
(c) 30 mins
(d) 35 mins​

Answer 1

50 Mins

First, we'll find for 1 Km.

1 Km = 90 / 150 Mins (After converting to mins)

1 Km = 1.666666666667

Therefore, 30 KM = 30*1.66666666667 = 50

Answer 2

Answer:

it taks 50 min to cover 30 km

Step-by-step explanation:

Distance = 90 km Time = 2.5 hours

speed = distance/time

speed = 90/2.5

Speed = 36 km/hr

speed=36*5/18

speed= 10 m/s

Distance = 30 km Speed = 10 m/s

Speed= Distance/Time

10=30000/Time

Time= 30000/10

Time= 30000 sec

Time = 30000/60

Time = 50 min.