Question

15.) How long a train will take to travel a distance of
200 km with a speed of 60 km h-1?
ans
16.) A boy travels with a speed of 10 m s-l for
30 minute. How much distance does he travel ?
ans​

Answer 1

Answer:

Ans:15)3h20min.

Ans:16)18 km

Explanation:

Ans:15) Distance covered by train = 200 km

Speed of train = 60 km h-1

We know speed = Distance/Time

⇒   60 = 200/Time

Time = 200/60 = 20/6 = (10/3) hours

= (3.1/3) hours = 3h + (1/3) hours

= 3h + (1/3) ×   60 min

= 3h + 20 min

= 3h 20 min Ans.

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Ans:16) Speed of boy = 10 m s-1

Time taken = 30 minutes

speed = distance travelled / time taken

Distance travelled = Speed × Time taken

Convert 30 minutes to seconds

1 minute = 60 sec

30 minute 60 × 30 = 1800 seconds

Putting the value of speed and time we get

Distance travelled = 10 ms-1 × (1800 sec) = 18000 m

= 18000 metre or 18 km Ans.

Answer 2

Answer :

Question 1 : How long a train will take to travel a distance of 200 km with a speed of 60 km per hour ?

Solution 1 :

• Distance = 200 km
• Speed = 60 km/hr

Now, We know that, Speed = Distance/Time.

⇒ 60 = 200/Time

⇒ Time*60 = 200

⇒ Time = 200/60

⇒ Time = 20/6

⇒ Time = 3.33 hours

Hence, The time taken by the train to travel a distance of 200 km with a speed of 60 kilometre per hour will be 3.33 hours.

Question 2 : A boy travels with a speed of 10 metre per second for 30 minutes. How much distance does he travel ?

Solution 2 :

Converting 3 minutes into seconds -

⇒ 3 × 60

⇒ 180 seconds

Now, We know that, Speed = Distance/Time.

• Speed = 10 m/s
• Time = 180 seconds

So, 10 = Distance/180

⇒ Distance = 10 × 180

⇒ Distance = 1800 m

Hence, The distance travelled by the boy with the speed of 10 metre per second for 30 minutes is 1800 m.