4MA0 Higher June 2011 Paper 3 Q19
19 \(P\) is directly proportional to the cube of \(Q\).
When \(Q = 15\), \(P = 1350\)
(a) Find a formula for \(P\) in terms of \(Q\). (3)
(b) Calculate the value of \(P\) when \(Q = 20\) (1)
| Scheme | Marks |
|---|---|
| \(P = kQ^3\) | M1 |
| \(1350 = k \times 3375\) | M1 |
| \(P = 0.4Q^3\) oe | A1 |
| (3) |
Notes
M1: for \(P = kQ^3\) but not for \(P = Q^3\)
M1: for \(1350 = k \times 3375\)
Also award for \(1350 = k \times 15^3\)
A1: \(P = 0.4Q^3\) oe
Award 3 marks if answer is \(P = kQ^3\) oe but \(k\) is evaluated as 0.4 in part (a) or part (b)
| Scheme | Marks |
|---|---|
| 3200 | B1 |
| (1) | |
| (Total 4 marks) |
Notes
B1: ft from “0.4” × 8000 except for \(k\) = 1, if at least M1 scored in (a) (at least 1 d.p. accuracy in follow through)