Mr M’s Edexcel GCSE Linear 1380 Higher Tier Calculator Paper 4 Answers Nov 2011

Mr M’s Edexcel GCSE Linear 1380 Higher Tier Calculator Paper 4 Answers November 2011


1. Calculator

a) 1.347909665 (2 marks)

b) 1.35 (1 mark)


2. Simple interest

£262.50 (3 marks)


3. Questionnaire

a) No time period and overlapping numbers in boxes (2 marks)

b) Improved question (2 marks)


4. Factors and multiples

a) 6 (1 mark)

b) 60 (2 marks)


5. Ratio

£6.40 (4 marks)


6. Angles

a) Show ... (3 marks)

b) i) x = 35

ii) 85 degrees (4 marks)


7. Equal areas

x = 5 (4 marks)


8. CD circles

a) 37.7 cm to 1 d.p. (you didn’t need to round) (2 marks)

b) 32 (2 marks)


9. Exchange rates

Paris (justification needed) (3 marks)


10. Mean from a frequency table

22.7 degrees C (4 marks)


11. Indices

a) $m^9$ (1 mark)

b) $p^6$ (1 mark)

c) $16n^12$ (2 marks)


12. Inequalities

a) -2, -1, 0, 1, 2, 3, 4 (2 marks)

b) $x>2.5$ (2 marks)


13. Linear graph

a) y values are 6, 4.5, 3, 1.5, 0, -1.5 (2 marks)

b) Draw graph (2 marks)

c) Gradient = -1.5 (2 marks)


14. Factorising

a) $2(3x+2)$ (1 mark)

b) $3xy(3x-5)$ (2 marks)


15. Moving averages

a) 36, 38 (2 marks)

b) The sales are increasing (1 mark)


16. Box plots

a) Median = 55 (1 mark)

b) Interquartile range = 23 (2 marks)

c) Draw box plot (2 marks)

d) Median of adults is higher and interquartile range for adults is bigger (2 marks)


17. Similar triangles

17.5 cm (3 marks)


18. Units of area

900 (2 marks)


19. Exact solutions

Decimal answers will NOT get full marks.
$x = \frac{7 \pm \sqrt{37}}{2}$ (3 marks)


20. Trigonometry

a) 9.06 cm (3 marks)

b) 12.6 cm (4 marks)


21. Histogram

a) Frequencies 40, 34, 24, 18, 12 (2 marks)

b) Draw bars 6 cm high and 4.5 cm high (2 marks)


22. Congruent triangles

Complete geometrical proof (3 marks)


23. Factorising and algebraic fraction

a) $(x+p)(x+q)$ (2 marks)

b) $(m+2)(m-2)$ (1 mark)

c) $\frac{x+10}{(x-4)(x+3)}$ (3 marks)


24. Solid hemisphere

603 (3 marks)


25. Lower bound

255000 (3 marks)


I still don’t want to guess grade boundaries – sorry!

hi sorry i'm new here, do you have the questions for these answers?

hi sorry i'm new here, do you have the questions for these answers?

Does anyone have the paper? Can u send it to me?

Does anyone know where I can get the calcualtor paper for november 2011?

I got 187. so pleased because i missed out the back page on the non-calc.

Let me try to explain.

If you could melt down the area and use it all up then the answer would be 44.

However, you were just told to cut the CDs out of a rectangle. Not all of the rectangle will be used.

Each CD has a diameter of 12 cm so you can fit 8 in one row (8 x 12 cm = 96 cm).

There are 4 rows (4 x 12 cm = 48 cm).

8 x 4 = 32.

Let me try to explain.

If you could melt down the area and use it all up then the answer would be 44.

However, you were just told to cut the CDs out of a rectangle. Not all of the rectangle will be used.

Each CD has a diameter of 12 cm so you can fit 8 in one row (8 x 12 cm = 96 cm).

There are 4 rows (4 x 12 cm = 48 cm).

8 x 4 = 32.

Let me try to explain.

If you could melt down the area and use it all up then the answer would be 44.

However, you were just told to cut the CDs out of a rectangle. Not all of the rectangle will be used.

Each CD has a diameter of 12 cm so you can fit 8 in one row (8 x 12 cm = 96 cm).

There are 4 rows (4 x 12 cm = 48 cm).

8 x 4 = 32.

I also found these if you would like to have a look:

http://mathworld.wolfram.com/CirclePacking.html
http://en.wikipedia.org/wiki/Circle_packing

Turns out what I mentioned is called hexagonal packing

Yes, I know the *real* answer is higher than 32. In the unofficial mark scheme I gave an answer that was accessible for Foundation students.

You suggested the answer might be 38. The official Edexcel mark scheme says 36 but they are wrong.

I have actually written an article about this that has been accepted for publication in a forthcoming issue of Mathematics in School. The true optimal answer is 33.

Yes, I know the *real* answer is higher than 32. In the unofficial mark scheme I gave an answer that was accessible for Foundation students.

You suggested the answer might be 38. The official Edexcel mark scheme says 36 but they are wrong.

I have actually written an article about this that has been accepted for publication in a forthcoming issue of Mathematics in School. The true optimal answer is 33.

How were you supposed to get 36 in there according to the real mark scheme?

Thank you for the answer. I think that the proof of this is way beyond my knowledge. May I ask how did you generate the image of those circles within the rectangle?

With great difficulty!

Precisely, and ,to me, it seems as if they have plucked a number out of thin air. What was the exact line of working GCSE students were supposed to use to get that number of 36?

Thanks.

The mark scheme isn't very illuminating.



Some of my students made a full-size model to investigate the problem!