Sequences: IGCSE Mathematics questions with answers
Free Sequences questions for IGCSE Mathematics (0580), part of Algebra & graphs. Each question has the answer and the marking points an examiner would look for.
Find the nth term of the sequence 6, 10, 18, 30, 46, …
[3]
(b)
Which term of the sequence is equal to 150?
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
2n2 − 2n + 6
second differences 4, so 2n2M1 remaining sequence linear: −2n + 6 M1 2n2 − 2n + 6 A1
3
(b)
the 9th term
2n2 − 2n + 6 = 150 solved M1 9 A1
2
Question 2Structured · 4 marks
Here are the first four terms of a sequence. 9, 11, 13, 15
(a)
Find the nth term.
[2]
(b)
Find the 20th term.
[1]
(c)
Show that 30 is not a term in the sequence.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
2n + 7
2n B1 2n + 7 B1
2
(b)
47
47 B1
1
(c)
non-integer n
solves nth term = value giving non-integer n B1
1
Question 3Structured · 3 marksA* challenge
The first term of a geometric sequence is 2 and the common ratio is 3.
(a)
Find the nth term.
[1]
(b)
Find the first term that is greater than 1000.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
2 × 3n − 1
2 × 3n − 1B1
1
(b)
1458
repeated multiplication or trial M1 1458 A1
2
Question 4Structured · 8 marksA* challenge
The first five terms of a sequence are 6, 13, 24, 39, 58, …
(a)
Find an expression, in terms of n, for the nth term.
[3]
(b)
Show that 468 is a term of the sequence and find its position.
[3]
(c)
Find the first term of the sequence that is greater than 1413.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
2n2 + n + 3
second difference 4 M1 2n2 used M1 2n2 + n + 3 A1
3
(b)
n = 15
2n2 + n − 465 = 0 M1 solve (factorise or formula) M1 n = 15 (positive integer) A1
3
(c)
1488 (the 27th term)
trial or solving the inequality M1 1488 A1
2
Question 5Structured · 5 marksA* challenge
(a)
Find the nth term of the sequence 1, −2, −3, −2, 1, …
[3]
(b)
Which term of the sequence is equal to 141?
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
n2 − 6n + 6
second differences 2, so n2M1 remaining sequence linear: −6n + 6 M1 n2 − 6n + 6 A1
3
(b)
the 15th term
n2 − 6n + 6 = 141 solved M1 15 A1
2
Question 6Structured · 3 marksA* challenge
The nth term of sequence P is 6n − 5. The nth term of sequence Q is 67 − 3n. The kth term of P is equal to the kth term of Q. Find k and the value of this term.
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in