Students often refer to Chapter 12 Racing Seconds Question Answer NCERT Solutions to verify their answers.

Class 5 Maths Chapter 12 Racing Seconds Question Answer Solutions

Racing Seconds Class 5 Maths Solutions

Class 5 Maths Chapter 12 Solutions

Raghav practices yoga in the morning.

Let Find Out (Pages 155-156)

Question 1.
At what time did Raghav start practising Yoga?
Answer:
5:35 a.m.

Question 2.
At what time did he finish?
Answer:
5:55 p.m.

Question 3.
How much time did he spend practising Yoga?
Answer:
Finishing time – starting time
= 5:55 a.m. – 5:35 a.m.
= 20 minutes

Question 4.
Find the time elapsed between the given time periods. Share your strategies.
(a) 01:15 p.m. to 01:42 p.m.?
(b) 03:18 p.m. to 08:18 p.m.?
(c) 09:15 a.m. to 11:30 a.m.?
Answer:
(a) By subtracting method.
Later time – earlier time
= 01:42 p.m – 0.1:15 p.m
= 27 minutes

(b) By subtracting method.
Later time – earlier time.
= 08:18 p.m. – 03:18 p.m.
= 05:00 hours.

(c) By number line method.

We jump
45 min + 1 hour + 30 min = 2 hours 15 minutes.

Question 5.
The table below shows the time taken by 3 children to paint a picture.

(a) Who took the longest time?
(b) Who took the least time?
Answer:
Times to paint:

• Raghav: 1 hour 20 minutes (80 min)
• Rani: 2 hours 10 minutes (130 min)
• Ritu: 1 hour 35 minutes (95 min)

(a) Rani took the longest (2 hr 10 min).
(b) Out of the three, Raghav was fastest with 1 hr 20 min.

Question 6.
Fill in the blanks by writing the time in the appropriate format.

Answer:

Question 7.
Match the following

Answer:

Let Us Do (Page 157)

Estimate whether you would take seconds or minutes to complete the following activities. Tick the appropriate cell.

Answer:

List events other than the ones listed above that you can do or that can happen in less than a minute or in a few seconds.
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Answer:

Estimate and verify how many of these you can do in a minute.

Answer:

Note: Answer may vary from student to student on their fitness and practice. –

Let Us Find (Page 158)

Question 1.
Find out the number of times you can skip the rope in 10 seconds.
Answer:
Try it yourself.

Question 2.
How long does it take you to write the word FRIEND?
Answer:
It takes about a second to write the word FRIEND.

Question 3.
How long does it take you to run 100 m?
Answer:
It takes about 18 to 22 seconds for an average student. It all depends on fitness and practice to run 100 m race.

Let Us Do (Page 159)

Observe the clocks and fill in the blanks.

Answer:

Draw the missing seconds hand on the clocks on the right side.

Answer:

Let us Do

Question 1.
Use the double number line below to complete the conversions.

Answer:

(b) Do as instructed. You can use the above double number line for the following conversions.
(i) 1 hours 10 minutes = _____ minutes
(ii) 2 hours 45 minutes = _____ minutes
(iii) 3 hours 15 minutes = _____ minutes
(iv) 4 hours 20 minutes = _____ minutes
(v) 75 minutes = ____ hour ____ minutes
(vi) 150 minutes = ____ hours ____ minutes
(vii) 220 minutes = ____ hours ____ minutes
(viii) 390 minutes = ____ hours ____ minutes
Answer:
(i) 1 hours 10 minutes = 70 minutes
(ii) 2 hours 45 minutes = 165 minutes
(iii) 3 hours 15 minutes = 195 minutes
(iv) 4 hours 20 minutes = 260 minutes
(v) 75 minutes = 1 hour 15 minutes
(vi) 150 minutes = 2 hours 30 minutes
(vii) 220 minutes = 3 hours 40 minutes
(viii) 390 minutes = 6 hours 30 minutes

(c) Fill in the blanks in the double number line to complete the conversions.

(i) 320 sec = ____ min ____ sec
(ii) 225 sec = ____ min ____ sec
(iii) 700 sec = ____ min ____ sec
(iv) 1,000 sec = ____ min ____ sec
(v) 10 min 13 sec = ____ sec
(vi) 4 min 8 sec = ____ sec
(vii) 15 min 40 sec = ____ sec
Answer:

Convert:
(i) 320 sec = 5 min 20 sec
(ii) 225 sec = 3 min 45 sec
(iii) 700 sec = 11 min 40 sec
(iv) 1000 sec = 16 min 40 sec
(v) 10 min 13 sec = 613 sec
(vi) 4 min 8 sec = 248 sec
(vii) 15 min 40 sec = 940 sec

Question 2.
Raghav studies Mathematics, English, Hindi, and The World Around Us subjects. He took 50 minutes to study each of the subjects. Find the total time taken in hours and minutes. Share your strategies with your class.
Answer:
Time taken by Raghav to study 1 subject = 50 min

Time taken by Raghav to study 4 subjects,
4 × 50 min= 200 min

By division Method

Divide 200 minutes by 60. (1 h = 60 min)
Here, quotient shows hours and remainder shows minutes.
Therefore, 200 minutes = 3 hours 20 min.

Question 3.
Raghu left his house at 08:00 hours and arrived at his Nana ji’s house at 09:05 hours. How long did he take to reach his house?

Answer:
Time at which Raghu left his house: 08:00 hours
Time at which he reached his Nanaji’s house: 09:05 hours
08:00 → 09:00 = 01 hour
From 08:00 to 09:05 = 1 hr 5 min.
Raghu took 01 hour 5 min to reach his Nanaji’s house.

Question 4.
Jyoti went to play at 06:15 PM. She came back after 1 hour 45 minutes. At what time did she reach home?
Answer:
Time at which Jyoti went to play: 06:15 pm
Time for which she played : 01 hour 45 minutes
Add 1 hr 45 min to 18:15 → 20:00 (8:00 pm.)
Jyoti returned at 8 pm after playing.

Question 5.
Ragini took 1 hour 10 minutes to do her homework. She finished it at 09:40 PM. What time did she start?
Answer:
Time taken by Ragini to complete her homework: 01 hr 10 min
Time at which she finished her homework: 09:40 pm
Time at which she started = 9:40 pm – 1 hr 10 min
09:40 pm – 01 hour = 08:40 pm
08:40 pm – 10 min = 08:30 pm
So, Ragini started at 08:30 pm.

Question 6.
A group of children left for a picnic at 08:30 AM. They returned after 4 hours and 10 minutes. At what time did they return?
Answer:
Time at which children left for picnic: 08:30 a.m
Duration of picnic: 04 hr 10 min
Time at which children returned = 08:30 + 04:10

Add four hours to 8:30
8:30 + 1 hr = 9:30
9:30 + 1 hr = 10:30
10:30 + 1 hr = 11:30 and
11:30 + 1 hr = 12:30
add 10 minutes in 12:30
12:30 + 10 min = 12:40
So they returned at 12:40 pm.

Question 7.
Raji started her homework at 06:00 PM. She finished her homework in 1 hour 30 minutes. At what time did she finish?
Answer:
Time at which Raji started her homework: 06:00 pm
Duration for which she did her homework: 01 hr 30 min
Time at which she finishes Add 1 hour in 6:00
= 06:00 + 01 hr = 07:00
Add 30 minutes to 7:00 = 7:30 pm
So, Raji finishes her homework at 07:30 pm.

Question 8.
Alya goes out to play at 05:30 PM and comes back after 1 hour 10 minutes. At what time does she come back?
Answer:
Time at which Alya goes for playing = 05:30 pm
Duration for which she plays = 01 hr 10 min
Time at which she returns Add 1 hour to 5:30
= 05:30 + 01 hr = 06:30
Add 10 minutes to 6:30
6:30 + 10 min = 6:40 pm
So, Ayla returns at 06:40 p.m.

Question 9.
If the lunch break of a school starts at 12:30 PM and ends in 35 minutes, what time will lunch end?
Answer:
Lunch Break of a school starts at: 12:30 pm
Duration of lunch break: 35 min (30 + 5) min

Lunch break ends at Add 30 minutes to 12:30
= 12:30 + 0:30 = 13:00, i.e. 1:00 pm.

Add 5 minutes to 1:00 – 1:00 + 5 min = 1:05
So, lunch break ends at 1:05 pm

Question 10.
It is 08:35 PM right now. What time will it be after 8 hours and 25 minutes?
Answer:
It is 8:35 pm right now
Let’s break it into = 4h + 4h + 25 min = 8 h 25 min.
Add first 4 hours to 8:35 pm
8:35 + 4 h = 12:35 AM
(Now it’s midnight, and we’ve moved into the next day.)
Add second 4 hours to 12:35 AM
12:35 + 4 h = 4:35 AM
Now add 25 minutes
4:35 + 25 = 5:00 AM