Chapter 8 of 15
Chapter 8: Tens and Ones
Uncle's Shop, Notes and Coins, Ring Throw & Token Cards | CBSE Session 2026–27
Core Pedagogical Competencies & Concepts
- Decomposing money amounts into ₹10 currency notes and ₹1 coins.
- Splitting 2-digit numbers into tens and ones (e.g. 19 = 10 + 9, 45 = 40 + 5).
- Ring throw game: calculating total score using red dots (10 points) and green dots (1 point).
- Token card representation: using square [10] and triangle [1] cards to count collections.
All Textbook Exercises & In-Text Tasks (19 Questions)
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Q1
Textbook Exercise • Money Breakdown
How many 10-rupee notes and 1-rupee coins do you need to pay for:
(a) A doll costing ₹18
(b) A water bottle costing ₹43
[2 Marks]
(a) A doll costing ₹18
(b) A water bottle costing ₹43
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
(a) ₹18 = One ₹10 note and 8 one-rupee coins.
(b) ₹43 = Four ₹10 notes and 3 one-rupee coins.
(a) ₹18 = One ₹10 note and 8 one-rupee coins.
(b) ₹43 = Four ₹10 notes and 3 one-rupee coins.
CBSE Step-by-Step Marking Scheme
(a) 1 note of ₹10 + 8 coins of ₹1
1 M
(b) 4 notes of ₹10 + 3 coins of ₹1
1 M
Q2
Textbook Exercise • How Much Money?
Count the total money:
(a) 3 notes of ₹10 and 5 coins of ₹1 = ₹______
(b) 6 notes of ₹10 and 2 coins of ₹1 = ₹______
[2 Marks]
(a) 3 notes of ₹10 and 5 coins of ₹1 = ₹______
(b) 6 notes of ₹10 and 2 coins of ₹1 = ₹______
✅ Step-by-Step Solution & Working
Answers:
(a) (3 × 10) + 5 = 30 + 5 = ₹35
(b) (6 × 10) + 2 = 60 + 2 = ₹62
(a) (3 × 10) + 5 = 30 + 5 = ₹35
(b) (6 × 10) + 2 = 60 + 2 = ₹62
CBSE Step-by-Step Marking Scheme
(a) ₹35
1 M
(b) ₹62
1 M
Q3
Textbook Exercise • Break-Up of Numbers
Break up the following numbers into tens and ones:
(a) 27 = 20 + 7
(b) 31 = ___ + ___
(c) 54 = ___ + ___
(d) 89 = ___ + ___
[3 Marks]
(a) 27 = 20 + 7
(b) 31 = ___ + ___
(c) 54 = ___ + ___
(d) 89 = ___ + ___
✅ Step-by-Step Solution & Working
Answers:
(b) 31 = 30 + 1
(c) 54 = 50 + 4
(d) 89 = 80 + 9
(b) 31 = 30 + 1
(c) 54 = 50 + 4
(d) 89 = 80 + 9
CBSE Step-by-Step Marking Scheme
(b) 30 + 1
1 M
(c) 50 + 4
1 M
(d) 80 + 9
1 M
Q4
Textbook Exercise • Bangle Throw Game
Karma and Gesar are playing a bangle throw game on a board with dots. Each RED dot counts for 10 points. Each GREEN dot counts for 1 point.
Karma's ring encircles 4 red dots and 4 green dots. What is Karma's total score?
[2 Marks]
Karma's ring encircles 4 red dots and 4 green dots. What is Karma's total score?
✅ Step-by-Step Solution & Working
Step-by-Step Calculation:
• 4 red dots = 4 × 10 = 40 points
• 4 green dots = 4 × 1 = 4 points
• Karma's total score = 40 + 4 = 44 points.
• 4 red dots = 4 × 10 = 40 points
• 4 green dots = 4 × 1 = 4 points
• Karma's total score = 40 + 4 = 44 points.
CBSE Step-by-Step Marking Scheme
Red dots = 40, Green dots = 4 shown
1 M
Total 44 points correct
1 M
Q5
Bangle Throw Game • Round 2
In round 2 of the bangle throw game, Gesar's ring encircles 3 red dots and 6 green dots. Karma's ring encircles 2 red dots and 8 green dots. Who won round 2?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• Gesar's score = (3 × 10) + 6 = 30 + 6 = 36 points.
• Karma's score = (2 × 10) + 8 = 20 + 8 = 28 points.
• Since 36 > 28, Gesar won round 2.
• Gesar's score = (3 × 10) + 6 = 30 + 6 = 36 points.
• Karma's score = (2 × 10) + 8 = 20 + 8 = 28 points.
• Since 36 > 28, Gesar won round 2.
CBSE Step-by-Step Marking Scheme
Gesar 36, Karma 28 calculated
1 M
Gesar identified as winner
1 M
Q6
NCERT Flute Man • Rat Token Cards
The Flute Man in the story uses cards to count the town's rats:
• A yellow square card [10] represents 10 rats.
• A blue triangle card [1] represents 1 rat.
Which cards will he use to show 23 rats?
[2 Marks]
• A yellow square card [10] represents 10 rats.
• A blue triangle card [1] represents 1 rat.
Which cards will he use to show 23 rats?
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• In 23, there are 2 tens and 3 ones.
• Flute Man uses: Two [10] cards and three [1] cards.
• In 23, there are 2 tens and 3 ones.
• Flute Man uses: Two [10] cards and three [1] cards.
CBSE Step-by-Step Marking Scheme
Two [10] cards identified
1 M
Three [1] cards identified
1 M
Q7
Token Card Decoding
What number of rats is shown by four [10] cards and seven [1] cards?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Calculation:
• 4 cards of [10] = 4 × 10 = 40
• 7 cards of [1] = 7 × 1 = 7
• Total number = 40 + 7 = 47 rats.
• 4 cards of [10] = 4 × 10 = 40
• 7 cards of [1] = 7 × 1 = 7
• Total number = 40 + 7 = 47 rats.
CBSE Step-by-Step Marking Scheme
40 + 7 shown
1 M
47 rats correct
1 M
Q8
Money Problem • School Canteen
Anita buys a samosa for ₹12 and a fruit juice for ₹15. How many 10-rupee notes and 1-rupee coins does she need to pay the total bill?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
1. Total cost = 12 + 15 = ₹27.
2. In ₹27, tens = 2 and ones = 7.
3. She needs two ₹10 notes and 7 one-rupee coins.
1. Total cost = 12 + 15 = ₹27.
2. In ₹27, tens = 2 and ones = 7.
3. She needs two ₹10 notes and 7 one-rupee coins.
CBSE Step-by-Step Marking Scheme
Total bill ₹27 calculated
1 M
2 notes of ₹10 + 7 coins of ₹1
1 M
Q9
Tens and Ones Addition
Add using tens and ones breakdown:
25 + 32 = (20 + 5) + (30 + 2)
[2 Marks]
25 + 32 = (20 + 5) + (30 + 2)
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• Add tens: 20 + 30 = 50
• Add ones: 5 + 2 = 7
• Total sum = 50 + 7 = 57.
• Add tens: 20 + 30 = 50
• Add ones: 5 + 2 = 7
• Total sum = 50 + 7 = 57.
CBSE Step-by-Step Marking Scheme
Tens sum (50) and ones sum (7) shown
1 M
Final sum 57 correct
1 M
Q10
Word Problem • Library Books
A librarian has 76 storybooks. How many bundles of 10 books can he tie? How many loose books will remain?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• In 76, tens = 7 and ones = 6.
• He can tie 7 bundles of 10 books.
• 6 loose books will remain.
• In 76, tens = 7 and ones = 6.
• He can tie 7 bundles of 10 books.
• 6 loose books will remain.
CBSE Step-by-Step Marking Scheme
7 bundles of 10
1 M
6 loose books
1 M
Q11
Money Thinking • Exact Change
If an item costs ₹30, what is the least number of 10-rupee notes you can use to pay without using any 1-rupee coins?
[1 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• 30 ÷ 10 = 3 notes of ₹10.
• 30 ÷ 10 = 3 notes of ₹10.
CBSE Step-by-Step Marking Scheme
3 notes of ₹10 identified
1 M
Q12
Place Value Reversal
What number has 6 in the ones place and 4 in the tens place? Is it 64 or 46?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• Tens place = 4 (value = 40)
• Ones place = 6 (value = 6)
• Number = 40 + 6 = 46 (not 64).
• Tens place = 4 (value = 40)
• Ones place = 6 (value = 6)
• Number = 40 + 6 = 46 (not 64).
CBSE Step-by-Step Marking Scheme
Tens and ones value written
1 M
46 correctly chosen
1 M
Q13
Mental Math • Quick Break
Can you break 19 into 10 + 9? Now write the break-up for: 11, 15, and 17.
[3 Marks]
✅ Step-by-Step Solution & Working
Answers:
• 11 = 10 + 1
• 15 = 10 + 5
• 17 = 10 + 7
• 11 = 10 + 1
• 15 = 10 + 5
• 17 = 10 + 7
CBSE Step-by-Step Marking Scheme
10 + 1
1 M
10 + 5
1 M
10 + 7
1 M
Q14
Token Card Exercise
A student drew five [10] cards and two [1] cards. Then his friend gave him one more [10] card and three [1] cards. What is his new total number?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• Initial cards = (5 × 10) + 2 = 52
• Added cards = (1 × 10) + 3 = 13
• New total = 52 + 13 = 65.
(Alternatively: 5 tens + 1 ten = 6 tens; 2 ones + 3 ones = 5 ones -> 65).
• Initial cards = (5 × 10) + 2 = 52
• Added cards = (1 × 10) + 3 = 13
• New total = 52 + 13 = 65.
(Alternatively: 5 tens + 1 ten = 6 tens; 2 ones + 3 ones = 5 ones -> 65).
CBSE Step-by-Step Marking Scheme
Step-by-step tens and ones addition
1 M
Total 65 calculated correctly
1 M
Q15
Comparative Value Problem
Which represents more money: 5 notes of ₹10 OR 40 coins of ₹1? Explain by finding both amounts.
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Solution:
• 5 notes of ₹10 = 5 × 10 = ₹50.
• 40 coins of ₹1 = 40 × 1 = ₹40.
• Since ₹50 > ₹40, 5 notes of ₹10 is more money (by ₹10).
• 5 notes of ₹10 = 5 × 10 = ₹50.
• 40 coins of ₹1 = 40 × 1 = ₹40.
• Since ₹50 > ₹40, 5 notes of ₹10 is more money (by ₹10).
CBSE Step-by-Step Marking Scheme
Both amounts ₹50 and ₹40 calculated
1 M
5 notes of ₹10 identified as more
1 M
Q16
Zero in Tens & Ones
What does the 0 represent in the number 70?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Explanation:
• In 70, the 0 represents zero ones.
• It acts as a place-holder to show that there are exactly 7 full tens and no loose units remaining.
• In 70, the 0 represents zero ones.
• It acts as a place-holder to show that there are exactly 7 full tens and no loose units remaining.
CBSE Step-by-Step Marking Scheme
Zero ones explained
1 M
Place-holder concept explained
1 M
Q17
Chapter Summary
Why is breaking numbers into tens and ones useful when adding or shopping?
[2 Marks]
✅ Step-by-Step Solution & Working
Summary:
1. Breaking into tens and ones simplifies mental calculation (we can add tens first, then ones).
2. In daily shopping, it directly matches real currency notes (₹10 notes) and coins (₹1 coins), making payment fast and error-free.
1. Breaking into tens and ones simplifies mental calculation (we can add tens first, then ones).
2. In daily shopping, it directly matches real currency notes (₹10 notes) and coins (₹1 coins), making payment fast and error-free.
CBSE Step-by-Step Marking Scheme
Mental addition simplification
1 M
Currency notes connection
1 M
Q18
Quick Quiz Problem
How many ₹10 notes make ₹100?
[1 Marks]
✅ Step-by-Step Solution & Working
Calculation:
• 100 ÷ 10 = 10 notes of ₹10.
• 100 ÷ 10 = 10 notes of ₹10.
CBSE Step-by-Step Marking Scheme
10 notes of ₹10 correct
1 M
Q19
Textbook Game • Bangles on Dots
In the bangle throw game, a red dot counts as 10 points and a green dot counts as 1 point. If Suraj's bangle encloses 3 red dots and 5 green dots, what is his total score?
[2 Marks]
✅ Step-by-Step Solution & Working
Step-by-Step Calculation:
• 3 red dots = 3 × 10 = 30 points.
• 5 green dots = 5 × 1 = 5 points.
• Total score = 30 + 5 = 35 points.
• 3 red dots = 3 × 10 = 30 points.
• 5 green dots = 5 × 1 = 5 points.
• Total score = 30 + 5 = 35 points.
CBSE Step-by-Step Marking Scheme
30 points from red dots
1 M
Total 35 points
1 M
🌟 NEP 2020 Competency-Based Case Study
Stationery Uncle's Exact Change Rule
Uncle runs a school bookshop. He tells children: 'I have only 10-rupee notes and 1-rupee coins. Give me exact money for your purchase.' Priya buys a notebook for ₹24, Aman buys a sketch pen set for ₹37, and Rohan buys a geometry box for ₹50.
Analytical Task: How many ₹10 notes and how many ₹1 coins must Priya give? How many ₹10 notes and ₹1 coins must Aman give? What must Rohan give?
Evaluation & Model Answer:
1. Priya (₹24): Two ₹10 notes (₹20) and 4 one-rupee coins (₹4).
2. Aman (₹37): Three ₹10 notes (₹30) and 7 one-rupee coins (₹7).
3. Rohan (₹50): Five ₹10 notes (₹50) and 0 one-rupee coins.
2. Aman (₹37): Three ₹10 notes (₹30) and 7 one-rupee coins (₹7).
3. Rohan (₹50): Five ₹10 notes (₹50) and 0 one-rupee coins.
Rubric: 1 M for Priya (2 notes + 4 coins) + 1 M for Aman (3 notes + 7 coins) + 1 M for Rohan (5 notes + 0 coins)