OCR MEI Paper 3 2020 November — Question 1 2 marks

Exam BoardOCR MEI
ModulePaper 3 (Paper 3)
Year2020
SessionNovember
Marks2
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicArithmetic Sequences and Series
TypeSigma notation: direct numerical evaluation
DifficultyEasy -1.2 This is a straightforward computation requiring evaluation of only 5 terms (r=1 to 5) with simple arithmetic: calculating 2^r(r-1) for each value and summing. No conceptual insight needed beyond understanding sigma notation, making it easier than average.
Spec1.04g Sigma notation: for sums of series

1 Find the value of \(\sum _ { r = 1 } ^ { 5 } 2 ^ { r } ( r - 1 )\).

Question 1:
AnswerMarks Guidance
AnswerMarks Guidance
BC: \(2\times0 + 4\times1 + 8\times2 + 16\times3 + 32\times4\)M1 At least two terms written out, allow one error, OR correct answer. Terms may not be seen as may be done completely on calculator
\(196\)A1
## Question 1:

| Answer | Marks | Guidance |
|--------|-------|----------|
| BC: $2\times0 + 4\times1 + 8\times2 + 16\times3 + 32\times4$ | M1 | At least two terms written out, allow one error, OR correct answer. Terms may not be seen as may be done completely on calculator |
| $196$ | A1 | |

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1 Find the value of $\sum _ { r = 1 } ^ { 5 } 2 ^ { r } ( r - 1 )$.

\hfill \mbox{\textit{OCR MEI Paper 3 2020 Q1 [2]}}