# Smart Charts

## Overview

In this chapter, students explore how to represent and understand data using tally marks, tables, bar charts, pie charts, and pictorial graphs. Through real-life examples such as pets, vehicles, family trees, plant growth, and TV advertisements, learners engage with meaningful contexts to develop skills in data collection, representation, and interpretation.

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## Key Topics Covered

### 1. Favourite Pet Animals (Tally Marks and Table)

* **Activity**: Yamini asked her classmates about their favourite pet animals and recorded responses using tally marks.
* **Tally Mark Concept**: 1 line for 1 child’s answer, with every 5th tally represented as a diagonal slash.
* **Objective**: Learn to count and group data efficiently using tally marks.

### 2. Traffic Count (Tally Marks for Vehicles)

* **Scenario**: Sumita stood on a road and counted types of vehicles for half an hour.
* **Types Included**: Cycles, cars, autos, buses, rickshaws, trucks.
* **Objective**: Practice counting with tally marks and converting tallies into numbers.

### 3. Helping at Home (Table and Pie Chart)

* **Survey**: Children reported tasks they help with at home.
* **Categories**: Cleaning, cooking, washing clothes/utensils, shopping.
* **Objective**: Use data to make a pie (chapati) chart; find fractions like one-third, one-fourth, etc.

### 4. After-School Activities (Data Collection)

* **Practice**: Students ask friends what they like doing after school and create a frequency table.
* **Examples**: Playing football, reading books, watching TV.
* **Objective**: Develop basic survey and categorization skills.

### 5. Advertisements on TV (Tally with Conditions)

* **Experiment**: Ragini counted ads during cartoon breaks, marked tally for total and dot for ads with children.
* **Discussion**: How ads use children as actors.
* **Objective**: Tally with special marking; critical thinking about media content.

### 6. Weather and Bar Charts

* **Cities**: Delhi, Shimla, Bangalore, Jaisalmer.
* **Dates**: 1st June and 1st December.
* **Skill**: Interpret bar charts to compare temperature across cities and seasons.
* **Objective**: Read bar charts and analyze climate variation.

### 7. Growth of Rabbits in Australia (Patterns and Sequences)

* **Concept**: Rabbits multiplied rapidly after being introduced to Australia.
* **Data Pattern**: Numbers increase more than double each year.
* **Objective**: Identify growth patterns and estimate future values.

### 8. Family Tree (Generations and Counting)

* **Visual**: Madhav learns about five generations through a family tree.
* **Activity**: Count number of elders in each generation (e.g., great-grandparents).
* **Objective**: Understand hierarchy and multiplication in family generations.

### 9. Growth Chart of a Plant (Line Graph)

* **Example**: Growth of a moong plant over 20 days, measured every 4 days.
* **Observation**: Compare growth between intervals, guess future growth.
* **Objective**: Plot and read line graphs; understand non-uniform growth.

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## New Terms and Simple Definitions

| Term | Definition |
| ------------------------- | --------------------------------------------------------------------- |
| Tally mark | A quick way of counting using lines grouped in sets of five |
| Bar chart | A graph that uses bars to show comparisons among categories |
| Pie chart (Chapati chart) | A circular chart divided into slices to show proportions |
| Advertisement | A message shown on TV or other media to promote something |
| Survey | A method of collecting information from people |
| Generation | A level in a family tree (e.g., grandparents, parents, children) |
| Line graph | A graph that uses points connected by lines to show changes over time |
| Pattern | A repeated or predictable change in numbers or shapes |


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## 🧮 Practice Sums

### 🟢 Easy (3 Questions)

**1.** Yamini used tally marks to record pets. If she wrote:
`|||| ||`
How many children chose this pet?

**Answer**: 7
**Explanation**: Each `|` is 1, and five lines `|||||` make 5. So `5 + 2 = 7`.

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**2.** In a family tree, how many grandparents does a person have?

**Answer**: 4
**Explanation**: Two parents → each has two parents → 2 × 2 = 4 grandparents.

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**3.** Look at this bar chart data:

* City A: 35°C
* City B: 20°C
Which city is hotter?

**Answer**: City A
**Explanation**: 35°C > 20°C.

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### 🟡 Medium (2 Questions)

**4.** Sumita saw the following vehicles on the road:
Cycle - `||||`
Bus - `||||| ||`
Car - `|||||`
How many vehicles did she see in total?

**Answer**: 4 (Cycle) + 7 (Bus) + 5 (Car) = 16
**Explanation**: Tally marks counted and added.

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**5.** In a survey:

* 25 children help with food
* Total children = 75
What fraction help with food?

**Answer**: 25/75 = 1/3
**Explanation**: Simplify the fraction by dividing both numbers by 25.

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### 🔵 Difficult (3 Questions)

**6.** Rabbits in Australia increased as follows:
Year 1 - 10
Year 2 - 18
Year 3 - 32
Estimate rabbits in Year 4 if the pattern continues.

**Answer**: 58
**Explanation**: Pattern shows rapid growth, almost doubling each year (18 → 32 → approx. 58).

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**7.** A plant grows:
Day 0 – 0 cm
Day 4 – 1.4 cm
Day 8 – 5.3 cm
On which day did it grow the most?

**Answer**: Between Day 4 and Day 8
**Explanation**: Growth = 5.3 - 1.4 = 3.9 cm (more than other intervals).

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**8.** If there are 2 great-grandparents for each grandparent, how many great-grandparents does a person have?

**Answer**: 8
**Explanation**: 4 grandparents × 2 = 8 great-grandparents.

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### 🔴 Very Difficult (2 Questions)

**9.** A bar graph shows:

* 1 June in Jaisalmer: 38°C
* 1 December in Jaisalmer: 25°C
What is the difference in temperature?

**Answer**: 13°C
**Explanation**: 38 - 25 = 13°C

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**10.** A plant’s growth data:

* Day 8: 5.3 cm
* Day 12: 9.5 cm
Guess the length on Day 10.

**Answer**: Around 7.4 cm
**Explanation**: Average growth between 8 and 12 is (9.5 - 5.3)/2 = 2.1 → 5.3 + 2.1 = 7.4 cm

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