OCR MEI C1 — Question 4 4 marks

Exam BoardOCR MEI
ModuleC1 (Core Mathematics 1)
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicIndices and Surds
TypeSolve power equations
DifficultyModerate -0.5 This is a straightforward algebraic rearrangement requiring expansion of brackets, collecting terms containing 'a', and factorising. It's slightly easier than average as it only tests basic manipulation skills with no conceptual depth, but the presence of multiple variables and the need to factorise prevents it from being trivial.
Spec1.02a Indices: laws of indices for rational exponents

Make \(a\) the subject of \(3(a + 4) = ac + 5f\). [4]

Question 4:
AnswerMarks
43a + 12 [= ac + 5f]
3a ac = 5f 12 or ft
a(3 c) = 5f 12 or ft
5f 12
[a ] oe or ft as final answer
AnswerMarks
3 cM1
M1
M1
M1
AnswerMarks
[4]for expanding brackets correctly
for collecting a terms on one side,
remaining terms on other
for factorising a terms; may be implied by
final answer
for division by their two-term factor;
for all 4 marks to be earned, work must be
AnswerMarks
fully correctannotate this question if partially correct
ft only if two a terms
ft only if two a terms, needing
factorising
may be earned before 2nd M1
Question 4:
4 | 3a + 12 [= ac + 5f]
3a ac = 5f 12 or ft
a(3 c) = 5f 12 or ft
5f 12
[a ] oe or ft as final answer
3 c | M1
M1
M1
M1
[4] | for expanding brackets correctly
for collecting a terms on one side,
remaining terms on other
for factorising a terms; may be implied by
final answer
for division by their two-term factor;
for all 4 marks to be earned, work must be
fully correct | annotate this question if partially correct
ft only if two a terms
ft only if two a terms, needing
factorising
may be earned before 2nd M1
Make $a$ the subject of $3(a + 4) = ac + 5f$. [4]

\hfill \mbox{\textit{OCR MEI C1  Q4 [4]}}