This 9th class maths chapter 8 online test covers Chapter 8 of the Class 9 Mathematics course, Logic. It has 25 multiple-choice questions, shown one at a time, and it marks itself the moment you finish. There is no timer and no sign-up. When you press finish you get your score, and every question is shown again with your answer, the correct option and a short explanation of why that option is right. An Urdu medium version of the same test is given further down this page.
What Chapter 8 Covers
The 25 questions are spread across the whole unit rather than one exercise, so the test is a fair check of whether you are ready for a class test or the annual paper:
- Inductive and deductive reasoning — drawing a general conclusion from a limited number of observations, as against reasoning from accepted truths to a particular case.
- Statements and truth values — what counts as a statement in logic, and deciding whether one is true or false.
- Logical operators — negation (~), conjunction (∧) and disjunction (∨), and how each one is read aloud.
- The conditional p → q — the antecedent and the consequent, and the single case in which a conditional is false.
- Converse, inverse and contrapositive — forming each one from a given conditional and knowing which are equivalent.
- The biconditional p ↔ q, truth tables, and testing two compound statements for logical equivalence.
- Axioms, postulates, conjectures and theorems — including the Fundamental Theorem of Arithmetic and the successor property of the natural numbers.
- Deductive proofs — worked proofs such as (A ∪ B)′ = A′ ∩ B′, expanding (x + 1)2 + 7, and adding the fractions a/b + c/d.
Revise These Before You Start
Logic is the one unit where a single misread word changes the answer. These are the rules the test keeps coming back to:
- A conjunction p ∧ q is true only when both p and q are true.
- A disjunction p ∨ q is false only when both p and q are false.
- A conditional p → q is false only when the antecedent p is true and the consequent q is false. In every other case it is true.
- A biconditional p ↔ q is true whenever p and q have the same truth value, and false when they differ.
- From p → q: the converse is q → p, the inverse is ~p → ~q, and the contrapositive is ~q → ~p. Only the contrapositive is logically equivalent to the original.
- Inductive reasoning moves from particular observations to a general rule and can be wrong. Deductive reasoning moves from accepted general truths to a particular conclusion and, if the steps are valid, cannot be.
- A conjecture is a statement believed true but not yet proved; once proved it becomes a theorem. Postulates are the statements accepted without proof in geometry.
How the Test Works
- 25 questions, one at a time, with Next and Previous buttons.
- No timer, so you can work through a truth table on paper before answering.
- Automatic marking the moment you finish.
- Answer review with the correct option and an explanation for every question.
- Retake as many times as you like, and your score is not stored anywhere.
Start the Chapter 8 Online Test
Chapter 8 is about being precise with language rather than calculating, so read every option word by word and watch for “only”, “not” and the direction of the arrow. Keep a pen and rough paper beside you: a two-line truth table settles most of these questions far faster than arguing with yourself. Aim for 20 out of 25 or better before you move on to the next unit.
Chapter 8 Online Test — Urdu Medium
Urdu medium students can attempt the same Chapter 8 test with every question, option and explanation written in Urdu. It behaves exactly like the English test above: 25 questions one at a time, no timer, and a full answer review at the end.
Mistakes Students Make in This Unit
When you look through your answer review, check whether any of your wrong answers came from these:
- Treating the converse q → p as equivalent to p → q — it is not. Only the contrapositive is.
- Calling a conditional false because its antecedent is false. A conditional with a false antecedent is true.
- Swapping inductive and deductive reasoning in the definition questions.
- Mixing up ∧ and ∨, which reverses the whole truth table.
- Calling an unproved statement a theorem when it is still only a conjecture.
- Negating a statement loosely instead of forming the exact logical negation.
What to Do After the Test
A score on its own teaches you very little. Go through the answer review properly and write down the number of every question you got wrong, along with the topic it came from. If two or three of them come from the same section of the unit, that section is what you revise next — not the whole chapter again. With logic in particular, build the truth table yourself for any operator you got wrong rather than rereading the definition, because the table is what the examiner is really testing. Then retake the test a day or two later rather than immediately, since answering correctly from memory is not the same as understanding it.
Frequently Asked Questions
What is the difference between inductive and deductive reasoning?
Inductive reasoning starts from a limited number of observations and generalises, so the conclusion is probable rather than certain. Deductive reasoning starts from statements already accepted as true and reasons to a particular case, so if the premises are true and the steps valid, the conclusion must be true.
When is a conditional statement false?
Only in one situation: when the antecedent is true and the consequent is false. If the antecedent is false, the conditional counts as true no matter what the consequent says, which surprises most students the first time they meet it.
What is the contrapositive, and why does it matter?
The contrapositive of p → q is ~q → ~p. It matters because it is logically equivalent to the original statement, so proving the contrapositive proves the original. The converse and the inverse are not equivalent to the original, though they are equivalent to each other.
Is a conjecture the same as a theorem?
No. A conjecture is a statement that looks true and has not been disproved, but has not been proved either. A theorem has a complete proof. A conjecture becomes a theorem the moment someone proves it.
Is this test free?
Yes. There is no sign-up, no limit on retakes and nothing is locked. Your score is not saved or shared.
Related Class 9 Maths Resources
Carry on with the Chapter 8 test paper for written practice, the Chapter 7 online test (Coordinate Geometry) or the Chapter 9 online test (Similar Figures). For full-length practice, download the 25 Class 9 Maths guess papers, each a complete 75-mark bilingual paper. You can also browse all Class 9 Maths test papers and every Class 9 Maths online test, or open the Class 9 Mathematics section for everything in one place.
Studying the other subjects too? There are self-marking chapter tests for Class 9 Physics and Class 9 Biology, and you can browse the whole Class 9 section by subject.