Time & Distance

Speed and Distance

The distance covered in unit time is speed.
Distance = speed x time,

Speed = Distance/ Time

Example Questions One

How many minutes Raman will take to cover a distance of 400 meters if he runs at a speed of 20 km/hr ?

a. 2 mins
b. 1.5 mins
c. 1⅕ mins
d. 2.5 mins
e. None of these
Answer & Explanation
Answer : [C]
Explanation :
⇒ Raman's speed = 20 km/hr = 20 × 5/18 = 50/9 m/sec
⇒ 400 × 9/50 = 1⅕ mins

Example Questions One

John travelled from his town to city. John went to city by bicycle at the speed of 25 km/h and came back at the speed of 4 km/h. If John took 5 hours and 48 min to complete his journey, what is the distance between town and city ?

a. 15 km
b. 22 km
c. 20 km
d. 25 km

Answer & Explanation
Answer : [C]
Explanation :
⇒ Average speed of John = 2xy/x+y = 2 × 25 × 4 / 25 + 4= 200/29 km/h
⇒ Distance traveled = Speed × Time = 200/29 × 29/5 = 40 Km
⇒ Distance between city and town = 40/2 = 20 km

Example Questions One

Ram walks at a speed of 12 km/h. Today the day was very hot so walked at ⅚ of his average speed. He arrived his school 10 minutes late. Find the usual time he takes to cover the distance between his school and home?

a.40 mins
b.45 mins
c.50 mins
d.60 mins
Answer & Explanation
Answer : [C]
Explanation :
⇒ If Ram is walking at ⅚ of his usual speed that means he is taking 6/5 of using time.
⇒ 6/5 of usual time - usual time = 10 mins
⇒ 1/5 of usual time = 10 mins
⇒ Usual time = 50 mins