What is the common difference in (9, 9, 9, 9, …)?
Answer and explanation
Correct answer: 0
For an arithmetic progression, the common difference is obtained by subtracting one term from the next, for example d = a₂ − a₁. In this sequence the first two terms are both 9, so d = 9 − 9 = 0. The same result is obtained from every consecutive pair because each term equals the next term. A constant sequence is therefore a valid arithmetic progression with zero common difference; an AP does not have to increase or decrease. Option A confuses a term with the difference. Option B would apply to a sequence that increases by one each time, and option D would represent a decrease of nine at each step. Thus option C is correct.
Frequently asked questions
What is the correct answer to this question?
0
Why is this the correct answer?
For an arithmetic progression, the common difference is obtained by subtracting one term from the next, for example d = a₂ − a₁. In this sequence the first two terms are both 9, so d = 9 − 9 = 0. The same result is obtained from every consecutive pair because each term equals the next term. A constant sequence is therefore a valid arithmetic progression with zero common difference; an AP does not have to increase or decrease. Option A confuses a term with the difference. Option B would apply to a sequence that increases by one each time, and option D would represent a decrease of nine at each step. Thus option C is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Arithmetic Progressions (AP). Topic: Introduction to APs and common difference..
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
