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Class 11 Sequences and Series worksheet
CBSE Mathematics. Geometric progressions, AM and GM, sums of n, n² and n³. Every sheet has 20 questions in three sections and an answer key, and the numbers change every time.
Sample questions
Real questions from this chapter, as the app sets them. Tap Answer to see the answer and working.
Section A · multiple choice
- 1.
The 5th term of the GP 1, 5, 25, … is:
- 625
- −625
- 125
- 3125
Answer
(a) 625
a r⁴ = 1 × (5)⁴
- 2.
The sum of the first 8 terms of the GP 5, −10, 20, … is:
- 855
- 1280
- −425
- −420
Answer
(c) −425
a(r⁸ − 1) ÷ (r − 1)
- 3.
The geometric mean of 1 and 441 is:
- 441
- 22
- 221
- 21
Answer
(d) 21
√(1 × 441) = √441
Section B · short answer
- 4.
For the GP 6, 24, 96, …, find the common ratio and the 9th term.
Answer
r = 4; 9th term = 393216
r = 24 ÷ 6
- 5.
Find the sum of the first 6 terms of the GP 16, 32/3, 64/9, ….
Answer
10640/243
S = a(1 − r⁶) ÷ (1 − r), a = 16, r = 2/3
Section C · long answer
- 6.
Find the sum Σ (k² + 3k + 5) for k = 1 to 7.
Answer
259
1 × Σk² + 3 × Σk + 5 × 7 = 1 × 140 + 3 × 28 + 35
Fresh sheets for your child
In the app, every Sequences and Series sheet is new: the app remembers the questions your child has already had and leaves them out. Print the sheet as a PDF, or use notebook mode and write the answers in a notebook.
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