Foundation November 2021 Paper 1 Q30
30 Write 200 as a product of prime factors.
Give your answer in index form. [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| 200 written as a product of factors where at least one factor is prime | M1 | eg 2 and 100 or \(2 \times 10^2\) or \(200 \div 5 = 40\) may be on a factor tree or repeated division allow one strand to be incorrect if a previous value completes the product eg \(10 \times 20\) followed by \(5 \times 2 \times 5 \times 6\) implies \(5 \times 2 \times 20\) for M1 |
| 2 and 2 and 2 and 5 and 5 | A1 | may be on a factor tree or repeated division |
| \(2^3 \times 5^2\) or \(5^2 \times 2^3\) | A1 |
Additional guidance
| Allow any number of 1s included as factors up to M1A1 only | |
| M1 may be awarded for correct work with no or incorrect answer, even if this is seen among multiple attempts | |
| \(1 \times 2^3 \times 5^2\) | M1A1A0 |
| \(2^3.5^2\) or \(2^3{\cdot}5^2\) or \(2^35^2\) or \(2^3,5^2\) | M1A1A1 |
| \(2 + 2 + 2 + 5 + 5\) | M1A1A0 |
| \(2^3 + 5^2\) | M1A1A0 |
| \(2 \times 2 \times 2 \times 5 \times 5\) and \(2^3 \times 5^2\) on answer line but \(2 \times 2 \times 2 \times 5 \times 5 = 2^3 \times 5^2\) on answer line | M1A1A0 M1A1A1 |
| \(2^3 \times 5^2 = 10^5\) | M1A1A0 |
| \(2^3 \times 5^2 = 200\) | M1A1A1 |
| \(8 \times 25\) with no prime factorisation | M0A0A0 |