Schooling · Class 7 · Mathematics · Arithmetic Expressions · Chapter on a page
CBSE Class 7 · Mathematics · NCERT Ganita Prakash
Arithmetic Expressions: chapter on a page
A cut of Shishya's notes for this chapter: the first paragraph of the introduction and the key ideas, formulas and facts, common mistakes and quick revision lists, word for word. Nothing is added or reworded; the worked examples are left out (they are on the chapter page).
About the notes: Written by Shishya's AI on 26 Sept 2026 from the chapter's title and class level, in Shishya's own words — not a copy or summary of the textbook. Read the official chapter for the book's own text, activities and exercises.
Fact-checked on 21 Oct 2026: an AI-assisted check of this note against cited sources; the errors it found were corrected that day. Some errors may remain.
Mind map
Drawn from the same notes by a fixed rule (no AI): each label is the item's own words — its bold term, its label before a colon, a short formula as written, or its first words.
The mind map as a list
- Key ideas
- An arithmetic expression contains…
- When an expression has more than one…
- Brackets tell us to do what is…
- Multiplication and division have the…
- Addition and subtraction also share…
- Writing a real-life problem as an…
- Two expressions that look different…
- Formulas and facts
- Order of operations (BODMAS rule)
- Key fact
- Brackets change the order
- No brackets and same priority
- Watch out for
- Doing addition before multiplication…
- Reading 12 ÷ 3 × 2 as 12 ÷ 6…
- Ignoring brackets and solving left…
- Writing 5 + 3 = 8 × 2 = 16 as a chain
- Forgetting that subtraction is the…
What this chapter is about
An arithmetic expression is a combination of numbers and operations like addition, subtraction, multiplication and division. For example, 5 + 3 × 2 is an arithmetic expression. In this chapter, you will learn how to read, write and evaluate such expressions correctly.
Key ideas
- An arithmetic expression contains numbers and operation symbols (+, −, ×, ÷) but no equals sign. Once you put an equals sign, it becomes an equation.
- When an expression has more than one operation, we follow a fixed order: first brackets, then multiplication and division (left to right), then addition and subtraction (left to right).
- Brackets tell us to do what is inside them first, before anything else.
- Multiplication and division have the same priority. We do them in the order they appear, moving from left to right.
- Addition and subtraction also share the same priority. We do them left to right after finishing multiplication and division.
- Writing a real-life problem as an arithmetic expression helps us solve it step by step without confusion.
- Two expressions that look different can still have the same value. For example, 2 × 6 and 4 + 8 both equal 12.
Formulas and facts to remember
- Order of operations (BODMAS rule):B – Brackets firstO – Orders (powers, but not in Class 7 scope here)D – Division (left to right)M – Multiplication (left to right)A – Addition (left to right)S – Subtraction (left to right)
- Key fact: Multiplication and division are done before addition and subtraction.
- Brackets change the order: The part inside brackets is always solved first.
- No brackets and same priority: Work left to right.
Common mistakes
- Doing addition before multiplication when there are no brackets → Remember: multiplication comes before addition unless brackets say otherwise.
- Reading 12 ÷ 3 × 2 as 12 ÷ 6 (grouping 3 × 2 first) → Do division and multiplication left to right; here, 12 ÷ 3 = 4 first, then 4 × 2 = 8.
- Ignoring brackets and solving left to right blindly → Always solve what is inside brackets before doing anything outside.
- Writing 5 + 3 = 8 × 2 = 16 as a chain → This misuses the equals sign; instead write each step on a new line or rewrite the full expression after each step.
- Forgetting that subtraction is the same as adding a negative when grouping → Keep the sign attached to the number that follows it.
Quick revision
- An arithmetic expression has numbers and operations but no equals sign.
- BODMAS: Brackets, then Division/Multiplication (left to right), then Addition/Subtraction (left to right).
- Brackets let you control which part to solve first.
- Multiplication and division have higher priority than addition and subtraction.
- Always work left to right for operations at the same level.