OCR MEI C1 — Question 10 4 marks

Exam BoardOCR MEI
ModuleC1 (Core Mathematics 1)
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCompleting the square and sketching
TypeRearrange to make variable subject (quadratic)
DifficultyModerate -0.5 This is a straightforward algebraic manipulation question requiring cross-multiplication and rearranging to isolate C. While it involves a fraction and collecting terms, it's a standard technique taught early in C1 with no conceptual difficulty, making it slightly easier than average.
Spec1.02c Simultaneous equations: two variables by elimination and substitution

Make \(C\) the subject of the formula \(P = \frac{C}{C + 4}\). [4]

Question 10:
AnswerMarks
104P −4P
[C =] or o.e.
AnswerMarks Guidance
1−P P−144 M1for PC + 4P = C
M1 for 4P = C − PC or ft
M1 for 4P = C (1 − P) or ft
4
B3 for [C =] oo.
1
−1
P
AnswerMarks
unsimplified4
Question 10:
10 | 4P −4P
[C =] or o.e.
1−P P−1 | 44 | M1for PC + 4P = C
M1 for 4P = C − PC or ft
M1 for 4P = C (1 − P) or ft
4
B3 for [C =] oo.
1
−1
P
unsimplified | 4
Make $C$ the subject of the formula $P = \frac{C}{C + 4}$. [4]

\hfill \mbox{\textit{OCR MEI C1  Q10 [4]}}