Class 5 Mathematics

Chapter 12 Solutions — Racing Seconds

Open Solutions PDF →Also seeTextbook page→

Open Solutions PDFReads in your browser→Also seeTextbook page→

Get the full experience in the app

Free practice, offline PDFs & solutions.

Already installed? Open in the app

Solutions

Overview

Step-by-step NCERT solutions for Racing Seconds (Chapter 12, NCERT Class 5 Mathematics) — every question and answer worked out in full, not just the final result. You can also read the Racing Seconds textbook chapter.

Solved

What these solutions cover

All 32 questions in Racing Seconds are solved in the PDF. Here's what's inside, exercise by exercise:

Let us find out — Yoga Clocks and Time Elapsed (p. 155–156)

At what time did Raghav start practising Yoga?
At what time did he finish?
How much time did he spend practising Yoga?
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.
5.
The table below shows the time taken by 3 children to paint a picture. Name | Time Taken Raghav | 1 hour 20 minutes Rani | 2 hours 10 minutes Ritu | 1 hour 35 minutes
- (a) Who took the longest time?
- (b) Who took the least time?
Fill in the blanks by writing the time in the appropriate format. Time in 12-hour format | Time in 24-hour format 05:30 a.m. | 05:30 hours ........... | 08:35 hours 11:55 a.m. | ........ hours 02:30 p.m. | 14:30 hours 05:30 p.m. | ........ hours 09:35 p.m. | ........ hours
Match the following. Time in 12-hour format | Time in 24-hour format 06:30 a.m. | 01:30 hours 08:45 p.m. | 23:45 hours 11:45 p.m. | 06:30 hours 04:30 a.m. | 20:45 hours 07:30 p.m. | 04:30 hours 01:30 a.m. | 19:30 hours

School Race — Seconds and the Race (p. 156–157)

Akira, Sunita, and Mary are participating in a 200 m walking race. Their stopwatches show: Place 1: 01:55 (Min:Sec) Place 2: 01:56 Place 3: 01:57 Identify the child who won the race. How much time did the child take?

Let Us Do — Seconds or Minutes? (p. 157–158)

Estimate whether you would take seconds or minutes to complete the following activities. Tick the appropriate cell. Activity | Seconds | Minutes Blinking of eyes | | Switching on and switching off the lights | | Counting from 1-20 | | Filling a glass from the tap | | Melting of an ice-cube | | Making a phone call | | Sitting down on the floor | | Drinking a glass of water | | Snapping fingers |…
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.
Estimate and verify how many of these you can do in a minute. Activity | Estimated Number | Actual Number Number of balloons blown | | Number of push-ups | | Number of breaths | | Number of hops on one leg | |

Let Us Find — Measuring Your Own Time in Seconds (p. 158)

Find out the number of times you can skip the rope in 10 seconds.
How long does it take you to write the word FRIEND?
How long does it take you to run 100 m?

Let Us Do — Observe the Clocks (Reading Seconds) (p. 159)

Observe the two clocks shown. Rani took ________ sec. to get out of her bed.
Observe the two clocks shown. Raghav took ________ sec. to move from his room to the kitchen.
Observe the two clocks shown. Ritu took ________ sec. to pick up a piece of paper from the floor.
Observe the two clocks shown. Raghu took ________ sec. to wash his spoon and plate.

Let Us Do — Draw the Missing Seconds Hand (p. 160)

Raghu took 20 sec. to read a sentence in his book. The left clock shows the start time (seconds hand at 12). Draw the missing seconds hand on the right clock.
Rani took 30 sec. to color a rectangle. The left clock shows the start (seconds hand at 12). Draw the missing seconds hand on the right clock.
Raghav took 60 sec. to move from his home to the garden. The left clock shows the start (seconds hand at 9). Draw the missing seconds hand on the right clock.
Ritu took 40 sec. to wash a plate. The left clock shows the start (seconds hand at 11). Draw the missing seconds hand on the right clock.

Let Us Do — Conversion of Hours to Minutes (p. 161–163)

1.
Use the double number line to complete the conversions.
- (a) Fill in the blanks on the double number line: 1 hr = 60 min, 2 hr = ___ min, 4 hr = ___ min, 7 hr = ___ min, ___ hr = 480 min, 9 hr = ___ min, ___ hr = 660 min, ___ hr = 720 min
- (b) Do the following conversions:
- (i) 1 hour 10 minutes = ___ minutes
- (ii) 2 hours 45 minutes = ___ minutes
- (iii) 3 hours 15 minutes = ___ minutes
- (iv) 4 hours…
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.
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 Nana ji's house?
Jyoti went to play at 06:15 PM. She came back after 1 hour 45 minutes. At what time did she reach home?
Ragini took 1 hour 10 minutes to do her homework. She finished it at 09:40 PM. What time did she start?
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?
Raji started her homework at 06:00 PM. She finished her homework in 1 hour 30 minutes. At what time did she finish?
Alya goes out to play at 05:30 PM and comes back after 1 hour 10 minutes. At what time does she come back?
If the lunch break of a school starts at 12:30 PM and ends in 35 minutes, what time will lunch end?
It is 08:35 PM right now. What time will it be after 8 hours and 25 minutes?

Sample

Worked examples

3 questions from Racing Seconds, solved step by step.

School Race — Seconds and the Race (p. 156–157)

Akira, Sunita, and Mary are participating in a 200 m walking race. Their stopwatches show: Place 1: 01:55 (Min:Sec) Place 2: 01:56 Place 3: 01:57 Identify the child who won the race. How much time did the child take?

1 min = 60 seconds, so each child took more than 1 minute.

The winner finishes in the LEAST time.

Place 1 shows 01:55 = 1 minute 55 seconds.

Place 2 shows 01:56 = 1 minute 56 seconds.

Place 3 shows 01:57 = 1 minute 57 seconds.

1 min 55 sec < 1 min 56 sec < 1 min 57 sec.

So the child standing on the first-place (centre) podium won.

The winning time is 1 minute 55 seconds.

Answer: The child on the first-place podium won. The winning time is 1 minute 55 seconds.

Let Us Do — Seconds or Minutes? (p. 157–158)

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.

This is an open activity — write your own examples.

Model answers (events that happen in a few seconds):

Clapping once, tying a shoelace knot, picking up a pencil, writing your name, jumping once, smiling, opening a door, turning a page of a book.

Answer: Model examples: clapping once, picking up a pencil, writing your name, opening a door, turning a book page. (Any correct short-duration activity is accepted.)

Let Us Do — Conversion of Hours to Minutes (p. 161–163)

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.

Number of subjects = 4.

Time per subject = 50 minutes.

Total time = 4 x 50 = 200 minutes.

Convert to hours and minutes:

200 / 60 = 3 remainder 20.

So 200 minutes = 3 hours 20 minutes.

Answer: Total time = 200 minutes = 3 hours 20 minutes.

All 32 questions in Racing Seconds are solved step by step in the Solutions PDF above.

Keep solving

Chapter 12 Solutions — Racing Seconds

Overview

What these solutions cover

Let us find out — Yoga Clocks and Time Elapsed (p. 155–156)

School Race — Seconds and the Race (p. 156–157)

Let Us Do — Seconds or Minutes? (p. 157–158)

Let Us Find — Measuring Your Own Time in Seconds (p. 158)

Let Us Do — Observe the Clocks (Reading Seconds) (p. 159)

Let Us Do — Draw the Missing Seconds Hand (p. 160)

Let Us Do — Conversion of Hours to Minutes (p. 161–163)

Worked examples

Akira, Sunita, and Mary are participating in a 200 m walking race. Their stopwatches show: Place 1: 01:55 (Min:Sec) Place 2: 01:56 Place 3: 01:57 Identify the child who won the race. How much time did the child take?

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.

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.

More solutions in Maths Mela

More NCERT Solutions for Class 5