The Cleanest Village – Class 4 Maths Chapter 7 Notes & NCERT PDF

Class 4MathematicsChapter 7NCERT book: Maths Mela - Class 4

Notes and a simple summary of Chapter 7 of the NCERT Class 4 Mathematics book, with the official chapter PDF, flashcards, an MCQ quiz and an AI tutor for your doubts.

🎧 Listen to the content

Chapter 7: The Cleanest Village

Introduction

Daisy and Lou study in Grade 4 in Shillong, Meghalaya. Their school plans a trip on 30 December 2025 to Mawlynnong, called Asia's cleanest village, in the East Khasi Hills, 79 km from Shillong. The poster says 77 families (414 people) of the Khasi tribe live there, the trip costs ₹500 per child, and the bus leaves at 7 am and returns at 4 pm. Attractions include the Jingmaham Living Root Bridge, the Church of the Epiphany and the Mawlynnong waterfall. The story is used to practise addition and subtraction of 2- and 3-digit numbers, with money and regrouping.

What's in this Chapter

Shopping with Sapan Dada: Prices for 1 kg: custard apple ₹45, radish ₹23, onion ₹32, potato ₹37, yam ₹45, sapota ₹70, papaya ₹65, banana ₹55. Children find costs such as 1 kg custard apple + 1 kg sapota = ₹115, 1 kg onion + 1 kg potato = ₹69, and 2 kg onion + 2 kg potato = ₹138, noticing the second is double the first. Their mother buys things for ₹163; children suggest what she might have bought.

Returning balance at Udaya Didi's store: Cost ₹113, paid ₹150, balance ₹37. Children find others: cost ₹185 paid ₹200 gives ₹15; cost ₹435 paid ₹500 gives ₹65; cost ₹149 paid ₹500 gives ₹351.

A strange puzzle: Four children each buy 2 oranges at ₹21 each (₹42). Krishna pays ₹50 and gets ₹8 back, Sudama pays ₹100 and gets ₹58, Mala pays ₹200 and gets ₹158, Neela pays ₹500 and gets ₹458.

Let Us Play: Place 1 to 6 on a triangle so each side adds to 9, then 10. Other sums are possible too (11 and 12), but 13 cannot be made.

Add up: 24 + 28 teachers = 52 teachers; 438 + 476 children = 914 children, shown with blocks and the column method. The book uses the word regrouping (10 Ones = 1 Ten, 10 Tens = 1 Hundred) instead of "carrying". Pusaw, a traditional Khasi snack made from red rice, costs ₹38 and ₹16, total ₹54. Piggy bank ₹185 plus ₹125 from mother gives ₹310.

Subtract it: 83 – 46 = 37 more children bought pusaw than fruit plates; 438 – 215 = 223 children still waiting to see the Living Roots Bridge; ₹310 – ₹179 = ₹131 spent. Regrouping 1 Ten as 10 Ones, or 1 Hundred as 10 Tens, is used when there are not enough to take away.

Let Us Solve: Ram Chacha's mangoes (527 – 264 = 263 more this year); Ranganna's dolls at Gombe Habba (639 – 531 = 108 left); a music school (78 + 532 = 610 boys, 95 + 346 = 441 girls); Preeti's cousin's school (423 + 178 = 601 children); library books (Rami read 236 pages and Kesu read 96 + 30 + 90 = 216, so Rami read 20 more; 128 – 23 = 105 pages of Feluda left); a Delhi to Aligarh train with passengers boarding and alighting; quick ways such as 410 – 12: 410 – 10 = 400 and 2 less is 398; number pair hunt and missing digits.

Key Ideas

Always estimate first, then calculate and check.

Add or subtract ones first, then tens, then hundreds.

Regroup 10 Ones as 1 Ten (and 10 Tens as 1 Hundred) while adding; break 1 Ten into 10 Ones while subtracting.

Balance = amount paid – cost.

Draw a picture of the story instead of hunting for key words.

Words to Learn

Add (जोड़ना), Subtract (घटाना)

Sum/Total (योग), Difference (अंतर)

Regroup (पुनः समूह बनाना)

Estimate (अनुमान)

Cost (कीमत), Balance (बचे पैसे/शेष राशि)

Price list (मूल्य सूची)

Village (गाँव)

Tips for Parents & Teachers

Take the child shopping and let them work out the total of two items and the change from a note.

Use play money for the orange puzzle and let the child count the change.

Ask the child to estimate before calculating: is 438 + 476 closer to 800 or 900?

Talk about keeping our village or colony clean, like Mawlynnong.

Common Mistakes

Forgetting to regroup, for example writing 24 + 28 = 412.

Subtracting the smaller digit from the bigger in every column (for 83 – 46 writing 43).

Starting from the hundreds instead of the ones place.

Mixing up cost and balance in money problems.

💡 Key Learning Points

✓Addition and subtraction of 2- and 3-digit numbers can be done with blocks, tokens and the column method.
✓Regrouping means changing 10 Ones into 1 Ten or 1 Ten into 10 Ones, and so on.
✓Estimating before calculating helps check whether an answer makes sense.
✓Balance to be returned = amount paid – cost.
✓Word problems become easier when we draw a picture of the situation.

👨‍🏫 Teaching Tips

→Show Meghalaya on a map and talk about Mawlynnong and the living root bridges before starting sums.
→Set up a pretend vegetable cart with Sapan Dada's price list and play money.
→Use Dienes blocks or tokens first, then connect each step to the column method.
→Say 'regroup' rather than 'carry' and 'borrow', as the book suggests.
→Ask children to estimate before every problem and compare with the exact answer.
→Let children make their own word problems for a sum of 856 and a difference of 563.

📋 Assessment Questions

Can the child add 3-digit numbers with regrouping, such as 438 + 476?
Can the child subtract with regrouping, such as 310 – 179?
Can the child work out the balance when a note is given for a purchase?
Can the child estimate an answer before calculating?
Can the child solve a two-step word problem like the library books question?

Ask the AI tutor about Class 4 Mathematics Chapter 7

Get question answers, important questions, a quick MCQ quiz or a simple explanation of “The Cleanest Village”. Free — sign in with Google.

How the AI tutor works →