Which explicit rule is correct for the sequence (11, 22, 33, 44, …)?
Answer and explanation
Correct answer: aₙ = 11n
An explicit rule gives the value of any term directly from its position n. In this sequence, the first term is 11, the second is 22, the third is 33, and the fourth is 44. Each term is 11 times its position: 11 × 1 = 11, 11 × 2 = 22, 11 × 3 = 33, and 11 × 4 = 44. Therefore the general rule is aₙ = 11n, so option C is correct. Option A gives 11 for n = 1 but then gives 21 for n = 2, while option B gives 12 for the first term. Option D gives 22 as the first term, so it does not match the sequence.
Frequently asked questions
What is the correct answer to this question?
aₙ = 11n
Why is this the correct answer?
An explicit rule gives the value of any term directly from its position n. In this sequence, the first term is 11, the second is 22, the third is 33, and the fourth is 44. Each term is 11 times its position: 11 × 1 = 11, 11 × 2 = 22, 11 × 3 = 33, and 11 × 4 = 44. Therefore the general rule is aₙ = 11n, so option C is correct. Option A gives 11 for n = 1 but then gives 21 for n = 2, while option B gives 12 for the first term. Option D gives 22 as the first term, so it does not match the sequence.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Sequences and Progressions. Topic: Explicit or general rule.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
