Higher June 2018 Paper 1 Q8
8 \(A = 3^5 \times 5 \times 7^3\)
\(B = 2^3 \times 3 \times 7^4\)
(a)
(i) Find the Highest Common Factor (HCF) of \(A\) and \(B\).
(ii) Find the Lowest Common Multiple (LCM) of \(A\) and \(B\). (2)
\(A = 3^5 \times 5 \times 7^3\)
\(B = 2^3 \times 3 \times 7^4\)
\(C = 2^p \times 5^q \times 7^r\)
Given that
- the HCF of \(B\) and \(C\) is \(2^3 \times 7\)
- the LCM of \(A\) and \(C\) is \(2^4 \times 3^5 \times 5^2 \times 7^3\)
(b) find the value of \(p\), the value of \(q\) and the value of \(r\). (2)
| Scheme | Marks |
|---|---|
| (i) \(3 \times 7^3\) | B1 |
| (ii) \(2^3 \times 3^5 \times 5 \times 7^4\) | B1 |
| (2) |
Notes
B1: for \(3 \times 7^3\) oe or 1029
B1: for \(2^3 \times 3^5 \times 5 \times 7^4\) oe or 23 337 720
| Scheme | Marks |
|---|---|
![]() Answer: 4, 2, 1 | M1 |
| A1 | |
| (2) | |
| (4 marks) |
Notes
M1: for \(r = 1\)
or for \(p = 4\) and \(q = 2\)
or correct representation of \(C\) in terms of prime factors on a Venn diagram
