Paper 2 tests reasoning more than knowledge. If any of these trip you up, read our free lesson on the logic of arguments first.
Try each question without a calculator, allowing about 4 minutes, then open the solution.
Question 1. Which statement is the contrapositive of “if n2 is even, then n is even”?
Answer: B. The contrapositive of “if P then Q” is “if not Q then not P”. Here: if n is not even, then n2 is not even. Trap: option A is the converse, which is a different statement.
Question 2. For real x, the condition x > 2 is ___ for x2 > 4.
Answer: B. If x > 2 then certainly x2 > 4, so it is sufficient. But x = −3 gives x2 > 4 without x > 2, so it is not necessary.
Question 3. Which is the negation of “every prime number greater than 2 is odd”?
Answer: C. The negation of “for all, P” is “there exists one for which P fails”. So: some prime greater than 2 is not odd, i.e. is even. Trap: “every prime is even” is far stronger than the negation.
Question 4. A “proof” that 1 = 2: (I) Let a = b. (II) Then a2 = ab. (III) So a2 − b2 = ab − b2. (IV) Factorise: (a + b)(a − b) = b(a − b). (V) So a + b = b, i.e. 2b = b, and 1 = 2. Which step is invalid?
Answer: D. Step V divides both sides by a − b, which is 0 because a = b. Dividing by zero is not allowed. Steps II to IV are all correct.
The Admit Maths course has 12 modules mapped to the official specification, worked solutions for every question, and two full timed mock papers. It opens in December 2026, in time for the January sitting.
One email when the course opens, plus occasional free practice. Unsubscribe any time. See our privacy notice.