Foundation June 2018 Paper 2 Q21
21
(a) Find the lowest common multiple (LCM) of 40 and 56 (2)
\(A = 2^3 \times 3 \times 5 \qquad\qquad B = 2^2 \times 3 \times 5^2\)
(b) Write down the highest common factor (HCF) of \(A\) and \(B\). (1)
| Answer | Mark | Mark scheme |
|---|---|---|
| 280 | M1 | for listing at least 3 multiples of both 40 and 56 OR finds the prime factors of both 40 and 56 |
| A1 | cao |
Additional guidance
40, 80, 120, … 56, 112, 168, …
OR 2,2,2,5 and 2,2,2,7
| Answer | Mark | Mark scheme |
|---|---|---|
| 60 | B1 | 60 or \(2^2 \times 3 \times 5\) oe |
Additional guidance
\(2^2\), 3, 5 not enough ie must be a product