# Let Us Count

## Overview

In the chapter **“Let Us Count,”** students explore different ways of counting through real-life objects and patterns. They learn to group, count efficiently, identify number types (even or odd), and recognize numerical patterns using play money, trays, and everyday items. The chapter emphasizes pattern recognition, logic, and classification skills.

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## Key Topics Covered

### 1. Counting with Objects

- **Scenario-Based Counting**: Children count cups made by Muniamma and coconuts plucked by Gundappa.
- **Group-Based Thinking**: Learners are encouraged to use multiplication or repeated addition to find total numbers (e.g., 5 coconuts from each tree).
- **Food Items in Trays**: Students count coconut laddoos and milk pedas arranged in identical trays, reinforcing equal grouping.

### 2. Patterns Using Money

- **Coin Arrangement**: Students analyze how Shirley and Shiv arranged coins in triangle patterns.
- **Task**: Determine total money in each pattern.
- **Hands-on Activity**: Use play money to show ₹36, ₹125, and ₹183 using denominations of ₹1, ₹2, ₹5, and ₹10.

### 3. Even and Odd Numbers

- **Definition through Grouping**:
- **Even Numbers**: Can be grouped in pairs (e.g., 2, 4, 6…)
- **Odd Numbers**: Have one left when paired (e.g., 1, 3, 5…)
- **Visual Learning**: Pairing crayons and using triangle patterns help students observe even and odd arrangements.
- **Explore Patterns**:
- Odd number always has even numbers before and after.
- Even number always has odd numbers before and after.

### 4. Identification and Sorting

- **Activities**:
- Identify numbers between 1 and 20 as even or odd.
- Circle odd numbers and square even numbers in a large table of values (from 1 to 100).
- Use digits to make two-digit numbers and identify them as even or odd.

### 5. Logical Questions and Reasoning

- **Observation**: Shirley finds page numbers of her book alternate between odd and even.
- **Experimentation**: Students pick 10 consecutive numbers and mark each as even or odd.
- **Critical Thinking**: Are there more odd or even numbers between 1 and 100? Students reason and discuss.

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## New Terms and Definitions

| Term | Simple Definition |
|---------------|-------------------|
| even number | A number that can be divided into pairs with nothing left (e.g., 2, 4, 6) |
| odd number | A number that cannot be divided into pairs without one left (e.g., 1, 3, 5) |
| grouping | Putting things into equal sets |
| pattern | A repeated design or arrangement |
| triangle | A shape with three sides |
| play money | Fake coins or notes used for learning |
| pairing | Matching two things together |
| consecutive | Numbers that come one after another without skipping |

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## Practice Questions

### Easy (3 Questions)
1. Count the total cups if each tray has 5 and there are 3 trays.
- **Answer**: 5 × 3 = 15 cups

2. Is 7 an even or odd number?
- **Answer**: Odd (cannot be grouped in pairs)

3. Which number is even: 18 or 19?
- **Answer**: 18

### Medium (2 Questions)
4. Arrange coins of ₹2 and ₹10 to make ₹36. How many coins of each can you use?
- **Answer**: ₹10 × 3 = ₹30 and ₹2 × 3 = ₹6 → Total = ₹36 (3 ₹10 coins and 3 ₹2 coins)

5. Use the digits 1 and 6 to make a two-digit number. Is it even or odd?
- **Answer**: 16 is even (ends in 6); 61 is odd (ends in 1)

### Difficult (3 Questions)
6. Identify all even numbers between 21 and 30.
- **Answer**: 22, 24, 26, 28, 30

7. A box has 6 trays. Each tray has 4 laddoos. How many laddoos in all?
- **Answer**: 6 × 4 = 24 laddoos

8. Circle odd numbers and square even ones: 51, 30, 43, 38, 52
- **Answer**: 51 (O), 30 (E), 43 (O), 38 (E), 52 (E)

### Very Difficult (2 Questions)
9. Are there more even or odd numbers between 1 and 100?
- **Answer**: Equal (50 even, 50 odd)

10. Choose any 10 consecutive numbers and mark even and odd. What do you notice?
- **Answer**: They alternate between even and odd (e.g., 11–20: odd, even, odd…)