GCSE · Integers, powers & roots

Factors, multiples and prime numbersExam-style questions

What a factor and a multiple are and how to keep them the right way round, how to list every factor of a number in pairs, why 1 is not prime and 2 is the only even prime, the primes up to 50, square and cube numbers on sight, and how one counter-example settles an "Is she correct?" question.

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14 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAll Level 1 Level 2 Level 3 Level 4

1
Show that $91$ is not a prime number.

(1 mark)
Level 2 · 1 markTry it
2
Find a number between $40$ and $60$ that is a multiple of $4$ and a multiple of $6$

(2 marks)
Level 2 · 2 marksTry it
3
Zara says,

" $1$ is a prime number, because it can only be divided by $1$ and by itself."

Is Zara correct?

You must give a reason for your answer.

(1 mark)
Level 2 · 1 markTry it