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Date May 2017 Marks available 3 Reference code 17M.1.SL.TZ2.T_5
Level Standard Level Paper Paper 1 (with calculator from previous syllabus) Time zone Time zone 2
Command term Find Question number T_5 Adapted from N/A

Question

Tomás is playing with sticks and he forms the first three diagrams of a pattern. These diagrams are shown below.

M17/5/MATSD/SP1/ENG/TZ2/05

Tomás continues forming diagrams following this pattern.

Tomás forms a total of 24 diagrams.

Diagram n is formed with 52 sticks. Find the value of n .

[3]
a.

Find the total number of sticks used by Tomás for all 24 diagrams.

[3]
b.

Markscheme

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

4 + 3 ( n 1 ) = 52     (M1)(A1)

 

Note:     Award (M1) for substitution into the formula of the n th term of an arithmetic sequence, (A1) for correct substitution.

 

n = 17     (A1)     (C3)

[3 marks]

a.

24 2 ( 2 × 4 + 23 × 3 ) OR 24 2 ( 4 + 73 )     (M1)(A1)(ft)

 

Notes:     Award (M1) for substitution into the sum of the first n terms of an arithmetic sequence formula, (A1)(ft) for their correct substitution, consistent with part (a).

 

924     (A1)(ft)     (C3)

 

Note:     Follow through from part (a).

 

[3 marks]

b.

Examiners report

[N/A]
a.
[N/A]
b.

Syllabus sections

Topic 1—Number and algebra » SL 1.2—Arithmetic sequences and series
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Topic 1—Number and algebra

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