Chapter 13 of 14
Chapter 13: Time Goes On
Clocks, Reading Time (Hours & Minutes), AM/PM & Daily Activity Schedules | CBSE Session 2026–27
Core Pedagogical Competencies & Concepts
- Understanding clock hands: hour hand (short) and minute hand (long).
- Reading time to the hour, half past (30 min), quarter past (15 min), and quarter to (45 min).
- Difference between AM (midnight to noon) and PM (noon to midnight).
- Calculating elapsed time between start and end of daily activities.
All Textbook Exercises & In-Text Tasks (18 Questions)
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Q1
Clock Reading • Quarter & Half Hours
What time is shown when: (a) The hour hand is between 3 and 4, and the minute hand points to 6? (b) The hour hand is just past 8, and the minute hand points to 3? (c) The hour hand is near 12, and the minute hand points to 9?
[3 Marks]
✅ Step-by-Step Solution & Working
Clock Readings:
• (a) Minute hand at 6 = 30 minutes. Time = 03:30 (Half past 3).
• (b) Minute hand at 3 = 15 minutes. Time = 08:15 (Quarter past 8).
• (c) Minute hand at 9 = 45 minutes (15 minutes to 12). Time = 11:45 (Quarter to 12).
• (a) Minute hand at 6 = 30 minutes. Time = 03:30 (Half past 3).
• (b) Minute hand at 3 = 15 minutes. Time = 08:15 (Quarter past 8).
• (c) Minute hand at 9 = 45 minutes (15 minutes to 12). Time = 11:45 (Quarter to 12).
CBSE Step-by-Step Marking Scheme
Correct reading for half past 3
1.0 M
Correct reading for quarter past 8
1.0 M
Correct reading for quarter to 12
1.0 M
Q2
Elapsed Time Calculation • Daily Routines
Meera started doing her math homework at 05:15 PM and finished at 06:05 PM. How many minutes did she spend on her homework?
[2 Marks]
✅ Step-by-Step Solution & Working
Calculation:
• Start time = 05:15 PM
• End time = 06:05 PM
1. From 05:15 PM to 06:00 PM = 60 - 15 = 45 minutes.
2. From 06:00 PM to 06:05 PM = 5 minutes.
• Total duration = 45 + 5 = 50 minutes.
• Start time = 05:15 PM
• End time = 06:05 PM
1. From 05:15 PM to 06:00 PM = 60 - 15 = 45 minutes.
2. From 06:00 PM to 06:05 PM = 5 minutes.
• Total duration = 45 + 5 = 50 minutes.
CBSE Step-by-Step Marking Scheme
Correct breakdown to the nearest hour
1.0 M
Correct total elapsed time (50 minutes)
1.0 M
Q3
AM vs PM • Classification
Write AM or PM for each activity: (a) Eating breakfast at 7:30 ___, (b) Playing in the park at 5:00 ___, (c) Sleeping at midnight 12:00 ___, (d) Lunch recess at school at 12:45 ___.
[2 Marks]
✅ Step-by-Step Solution & Working
Answers:
• (a) Breakfast at 7:30 AM (morning)
• (b) Playing in park at 5:00 PM (evening)
• (c) Sleeping at midnight 12:00 AM (start of day)
• (d) Lunch recess at 12:45 PM (afternoon).
• (a) Breakfast at 7:30 AM (morning)
• (b) Playing in park at 5:00 PM (evening)
• (c) Sleeping at midnight 12:00 AM (start of day)
• (d) Lunch recess at 12:45 PM (afternoon).
CBSE Step-by-Step Marking Scheme
Correct AM/PM classification for all 4 events
2.0 M
Q4
Analog Clock Face • Time Reading
Look at an analog clock face:
(a) Where does the hour hand and minute hand point at 4:15 (quarter past 4)?
(b) Where do they point at 7:30 (half past 7)?
(c) Where do they point at 9:45 (quarter to 10)?
[3 Marks]
(a) Where does the hour hand and minute hand point at 4:15 (quarter past 4)?
(b) Where do they point at 7:30 (half past 7)?
(c) Where do they point at 9:45 (quarter to 10)?
✅ Step-by-Step Solution & Working
Analog Clock Positions:
• (a) 4:15: The minute hand points directly at 3. The hour hand is slightly past 4.
• (b) 7:30: The minute hand points directly at 6. The hour hand is halfway between 7 and 8.
• (c) 9:45: The minute hand points directly at 9. The hour hand is close to 10.
• (a) 4:15: The minute hand points directly at 3. The hour hand is slightly past 4.
• (b) 7:30: The minute hand points directly at 6. The hour hand is halfway between 7 and 8.
• (c) 9:45: The minute hand points directly at 9. The hour hand is close to 10.
CBSE Step-by-Step Marking Scheme
Correct minute and hour hand positions for 4:15
1.0 M
Correct minute and hour hand positions for 7:30
1.0 M
Correct minute and hour hand positions for 9:45
1.0 M
Q5
Calendar Reading • Days and Months
Answer the following calendar questions:
(a) How many months in a year have exactly 31 days? Name any three.
(b) How many days does February have in a leap year and in an ordinary year?
(c) If 5th September is a Tuesday, what day of the week is 12th September?
[3 Marks]
(a) How many months in a year have exactly 31 days? Name any three.
(b) How many days does February have in a leap year and in an ordinary year?
(c) If 5th September is a Tuesday, what day of the week is 12th September?
✅ Step-by-Step Solution & Working
Calendar Facts:
• (a) 31-Day Months: There are 7 months with 31 days (January, March, May, July, August, October, December).
• (b) February: February has 29 days in a leap year and 28 days in an ordinary year.
• (c) Day Calculation:
- Since there are 7 days in a week, adding 7 days gives the same day of the week.
- 5 + 7 = 12th September is also a Tuesday.
• (a) 31-Day Months: There are 7 months with 31 days (January, March, May, July, August, October, December).
• (b) February: February has 29 days in a leap year and 28 days in an ordinary year.
• (c) Day Calculation:
- Since there are 7 days in a week, adding 7 days gives the same day of the week.
- 5 + 7 = 12th September is also a Tuesday.
CBSE Step-by-Step Marking Scheme
Correct count (7) and names of 31-day months
1.0 M
Correct February days (29 leap, 28 ordinary)
1.0 M
Correct day of the week deduction (Tuesday)
1.0 M
Q6
Duration of Daily Routines • Elapsed Time
Aman's daily schedule is as follows:
• Leaves for school: 7:30 AM
• Returns from school: 2:00 PM
(a) How many hours does Aman spend away at school?
(b) He plays football from 5:15 PM to 6:30 PM. What is the duration of his playtime?
[3 Marks]
• Leaves for school: 7:30 AM
• Returns from school: 2:00 PM
(a) How many hours does Aman spend away at school?
(b) He plays football from 5:15 PM to 6:30 PM. What is the duration of his playtime?
✅ Step-by-Step Solution & Working
Step-by-Step Elapsed Time:
(a) Time at School:
• From 7:30 AM to 12:00 noon = 4 hours 30 minutes.
• From 12:00 noon to 2:00 PM = 2 hours.
• Total school time = 4 hr 30 min + 2 hr = 6 hours 30 minutes.
(b) Playtime Duration:
• From 5:15 PM to 6:15 PM = 1 hour (60 minutes).
• From 6:15 PM to 6:30 PM = 15 minutes.
• Total playtime = 1 hour 15 minutes (or 75 minutes).
(a) Time at School:
• From 7:30 AM to 12:00 noon = 4 hours 30 minutes.
• From 12:00 noon to 2:00 PM = 2 hours.
• Total school time = 4 hr 30 min + 2 hr = 6 hours 30 minutes.
(b) Playtime Duration:
• From 5:15 PM to 6:15 PM = 1 hour (60 minutes).
• From 6:15 PM to 6:30 PM = 15 minutes.
• Total playtime = 1 hour 15 minutes (or 75 minutes).
CBSE Step-by-Step Marking Scheme
Correct school duration (6 hours 30 minutes)
1.5 M
Correct playtime duration (1 hour 15 minutes)
1.5 M
Q7
Age Timeline • Date of Birth Analysis
Kavya was born on 15th August 2018.
(a) How old was she on 15th August 2024?
(b) How old will she be on 15th August 2030?
(c) In which year did she celebrate her 5th birthday?
[3 Marks]
(a) How old was she on 15th August 2024?
(b) How old will she be on 15th August 2030?
(c) In which year did she celebrate her 5th birthday?
✅ Step-by-Step Solution & Working
Step-by-Step Timeline:
(a) Age in 2024:
• 2024 - 2018 = 6 years old.
(b) Age in 2030:
• 2030 - 2018 = 12 years old.
(c) 5th Birthday Year:
• 2018 + 5 = Year 2023.
(a) Age in 2024:
• 2024 - 2018 = 6 years old.
(b) Age in 2030:
• 2030 - 2018 = 12 years old.
(c) 5th Birthday Year:
• 2018 + 5 = Year 2023.
CBSE Step-by-Step Marking Scheme
Correct age in 2024 (6 years)
1.0 M
Correct age in 2030 (12 years)
1.0 M
Correct 5th birthday year (2023)
1.0 M
Q8
Textbook Exercise • Practical Problem Solving
In Chapter 13 ('Time Goes On'), a student solves an exercise problem: If 1 packet contains 12 items, how many items are in 4 such packets? Explain using repeated addition and multiplication.
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
1. Repeated addition: 12 + 12 + 12 + 12 = 48 items.
2. Multiplication fact: 4 × 12 = 48 items.
3. Both methods yield the exact same answer. Multiplication is efficient repeated addition.
1. Repeated addition: 12 + 12 + 12 + 12 = 48 items.
2. Multiplication fact: 4 × 12 = 48 items.
3. Both methods yield the exact same answer. Multiplication is efficient repeated addition.
CBSE Step-by-Step Marking Scheme
Repeated addition 12+12+12+12 = 48
1 M
Multiplication 4 × 12 = 48
1 M
Q9
In-Text Activity • Concept Exploration
In 'Time Goes On', how do you verify your mathematical calculations? Give an example using two numbers that add up to 100.
[2 Marks]
✅ Step-by-Step Solution & Working
Verification Method:
• Take two numbers: 65 and 35. Sum = 65 + 35 = 100.
• Verification by inverse operation (subtraction): 100 - 35 = 65, and 100 - 65 = 35.
• Since subtraction brings back the original numbers, the addition is confirmed correct.
• Take two numbers: 65 and 35. Sum = 65 + 35 = 100.
• Verification by inverse operation (subtraction): 100 - 35 = 65, and 100 - 65 = 35.
• Since subtraction brings back the original numbers, the addition is confirmed correct.
CBSE Step-by-Step Marking Scheme
Addition 65 + 35 = 100
1 M
Inverse check 100 - 35 = 65
1 M
Q10
Practice Time • Mental Math Drills
Solve mentally:
(a) 25 + 75 = ?
(b) 150 - 60 = ?
(c) Double of 45 = ?
(d) Half of 80 = ?
[2 Marks]
(a) 25 + 75 = ?
(b) 150 - 60 = ?
(c) Double of 45 = ?
(d) Half of 80 = ?
✅ Step-by-Step Solution & Working
Mental Calculations:
• (a) 25 + 75 = 100.
• (b) 150 - 60 = 90.
• (c) 45 × 2 = 90.
• (d) 80 ÷ 2 = 40.
• (a) 25 + 75 = 100.
• (b) 150 - 60 = 90.
• (c) 45 × 2 = 90.
• (d) 80 ÷ 2 = 40.
CBSE Step-by-Step Marking Scheme
All 4 mental math facts correct
2 M
Q11
Word Problem • Real Life Application
A school library received 3 boxes of mathematics activity books. Each box contained 25 books. During the week, 38 books were distributed to Grade 3 children. How many books remain in the library?
[3 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
1. Total books received = 3 × 25 = 75 books.
2. Books distributed = 38 books.
3. Books remaining = 75 - 38 = 37 books.
1. Total books received = 3 × 25 = 75 books.
2. Books distributed = 38 books.
3. Books remaining = 75 - 38 = 37 books.
CBSE Step-by-Step Marking Scheme
Total 3 × 25 = 75
1.5 M
Remainder 75 - 38 = 37
1.5 M
Q12
Critical Thinking • Finding the Pattern
Observe the sequence related to 'Time Goes On': 12, 24, 36, 48, ___, ___. Find the next two terms and state the mathematical rule.
[2 Marks]
✅ Step-by-Step Solution & Working
Pattern Analysis:
• 12 + 12 = 24
• 24 + 12 = 36
• 36 + 12 = 48
• Rule: Successive addition of 12 (Multiples of 12).
• Next terms: 48 + 12 = 60, 60 + 12 = 72.
• 12 + 12 = 24
• 24 + 12 = 36
• 36 + 12 = 48
• Rule: Successive addition of 12 (Multiples of 12).
• Next terms: 48 + 12 = 60, 60 + 12 = 72.
CBSE Step-by-Step Marking Scheme
Next terms 60, 72
1 M
Rule: multiples of 12 / +12 step
1 M
Q13
Estimation & Measurement • Practical Judgment
Estimate whether each measurement is greater than or less than 1 metre:
(a) Length of your classroom pencil.
(b) Height of your classroom teacher.
(c) Width of your mathematics textbook.
(d) Length of the school blackboard.
[2 Marks]
(a) Length of your classroom pencil.
(b) Height of your classroom teacher.
(c) Width of your mathematics textbook.
(d) Length of the school blackboard.
✅ Step-by-Step Solution & Working
Estimation:
• (a) Pencil: Less than 1 metre (approx. 15 cm).
• (b) Teacher height: Greater than 1 metre (approx. 1.6 to 1.7 m).
• (c) Textbook width: Less than 1 metre (approx. 20 cm).
• (d) Blackboard length: Greater than 1 metre (approx. 2 to 3 m).
• (a) Pencil: Less than 1 metre (approx. 15 cm).
• (b) Teacher height: Greater than 1 metre (approx. 1.6 to 1.7 m).
• (c) Textbook width: Less than 1 metre (approx. 20 cm).
• (d) Blackboard length: Greater than 1 metre (approx. 2 to 3 m).
CBSE Step-by-Step Marking Scheme
Correct estimation for all 4 items
2 M
Q14
Data Interpretation • Reading Simple Tables
A table shows student preferences for fruit: Apple (15), Banana (22), Mango (35), Orange (18).
(a) Which fruit is preferred by the maximum number of students?
(b) How many more students prefer Mango over Banana?
(c) What is the total number of students surveyed?
[3 Marks]
(a) Which fruit is preferred by the maximum number of students?
(b) How many more students prefer Mango over Banana?
(c) What is the total number of students surveyed?
✅ Step-by-Step Solution & Working
Table Interpretation:
• (a) Maximum preference: Mango with 35 students.
• (b) Difference: 35 - 22 = 13 more students prefer Mango.
• (c) Total students: 15 + 22 + 35 + 18 = 90 students.
• (a) Maximum preference: Mango with 35 students.
• (b) Difference: 35 - 22 = 13 more students prefer Mango.
• (c) Total students: 15 + 22 + 35 + 18 = 90 students.
CBSE Step-by-Step Marking Scheme
Mango identified
1 M
Difference = 13
1 M
Total = 90
1 M
Q15
Let us Do • Shapes and Symmetry
Draw a line of symmetry through each shape:
(a) A rectangle
(b) An equilateral triangle
(c) A circle.
How many lines of symmetry does a circle have?
[3 Marks]
(a) A rectangle
(b) An equilateral triangle
(c) A circle.
How many lines of symmetry does a circle have?
✅ Step-by-Step Solution & Working
Symmetry Properties:
• (a) A rectangle has 2 lines of symmetry (horizontal and vertical through centers of opposite sides).
• (b) An equilateral triangle has 3 lines of symmetry (from each vertex to opposite midpoint).
• (c) A circle has infinite lines of symmetry (any diameter passing through the center).
• (a) A rectangle has 2 lines of symmetry (horizontal and vertical through centers of opposite sides).
• (b) An equilateral triangle has 3 lines of symmetry (from each vertex to opposite midpoint).
• (c) A circle has infinite lines of symmetry (any diameter passing through the center).
CBSE Step-by-Step Marking Scheme
Rectangle = 2 lines
1 M
Triangle = 3 lines
1 M
Circle = infinite lines
1 M
Q16
Puzzle Time • Missing Number Grid
In a 3x3 magic square, the sum of each row, column, and diagonal is 15. The center number is 5. What numbers go in the opposite corners if one corner is 2?
[2 Marks]
✅ Step-by-Step Solution & Working
Magic Square Logic:
• In a 3x3 magic square with sum 15 and center 5, opposite corners must sum to 10 (since 2 + 5 + x = 15 → x = 8).
• If one corner is 2, the diagonally opposite corner must be 8.
• Other corner pairs: 4 and 6.
• In a 3x3 magic square with sum 15 and center 5, opposite corners must sum to 10 (since 2 + 5 + x = 15 → x = 8).
• If one corner is 2, the diagonally opposite corner must be 8.
• Other corner pairs: 4 and 6.
CBSE Step-by-Step Marking Scheme
Opposite corner = 8 with reasoning
2 M
Q17
Money & Shopping • Cash Memo Bill
Rani visits a stationery shop and buys: 2 Pencils at ₹5 each, 1 Eraser for ₹3, and 1 Notebook for ₹25. Prepare a simple cash memo showing total bill and change returned from a ₹50 note.
[3 Marks]
✅ Step-by-Step Solution & Working
Cash Memo Preparation:
• 2 Pencils @ ₹5 = ₹10
• 1 Eraser @ ₹3 = ₹3
• 1 Notebook @ ₹25 = ₹25
• Total Bill Amount = ₹10 + ₹3 + ₹25 = ₹38.
• Amount paid = ₹50.
• Change returned = ₹50 - ₹38 = ₹12.
• 2 Pencils @ ₹5 = ₹10
• 1 Eraser @ ₹3 = ₹3
• 1 Notebook @ ₹25 = ₹25
• Total Bill Amount = ₹10 + ₹3 + ₹25 = ₹38.
• Amount paid = ₹50.
• Change returned = ₹50 - ₹38 = ₹12.
CBSE Step-by-Step Marking Scheme
Correct item breakdown and total ₹38
2 M
Change = ₹12
1 M
Q18
Chapter Review • Comprehensive Concept Check
True or False:
(a) 1 kilometre is equal to 1000 metres.
(b) 500 millilitres is equal to half a litre.
(c) A square has 4 equal straight edges and 4 right-angled corners.
[3 Marks]
(a) 1 kilometre is equal to 1000 metres.
(b) 500 millilitres is equal to half a litre.
(c) A square has 4 equal straight edges and 4 right-angled corners.
✅ Step-by-Step Solution & Working
Review Answers:
• (a) True: 1 km = 1000 m.
• (b) True: 1 Litre = 1000 mL, so half a litre = 500 mL.
• (c) True: A square has 4 equal sides and 4 right angles.
• (a) True: 1 km = 1000 m.
• (b) True: 1 Litre = 1000 mL, so half a litre = 500 mL.
• (c) True: A square has 4 equal sides and 4 right angles.
CBSE Step-by-Step Marking Scheme
All 3 statements correctly evaluated as True
3 M
🌟 NEP 2020 Competency-Based Case Study
School Annual Sports Day Schedule
The 100m sprint race began at 10:20 AM and took 25 minutes. There was a 15-minute prize ceremony immediately following.
Analytical Task: At what time did the prize ceremony conclude? How many total minutes elapsed from the race start to the end of the ceremony?
Evaluation & Model Answer:
1. Race start = 10:20 AM.
2. Race finish = 10:20 AM + 25 min = 10:45 AM.
3. Ceremony finish = 10:45 AM + 15 min = 11:00 AM.
4. Total elapsed time = 25 + 15 = 40 minutes.
2. Race finish = 10:20 AM + 25 min = 10:45 AM.
3. Ceremony finish = 10:45 AM + 15 min = 11:00 AM.
4. Total elapsed time = 25 + 15 = 40 minutes.
Rubric: 1.5M chronological addition of times + 1.5M total duration calculation.