Which of the following list of numbers is/are an Arithmetic Progression?
(A) 6, 12, 18, 24...
(B) 1, 3, 5, 7...
(C) −3, 3, −3, 3...
(D) 21, 18, 15...
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A), (B) and (D) only
A list of numbers is an Arithmetic Progression (AP) when each term is obtained by adding the same fixed number (the common difference) to the term before it.
(A) 6, 12, 18, 24... An AP. Each term is 6 more than the one before: common difference 6.
(B) 1, 3, 5, 7... An AP. Each term is 2 more than the one before: common difference 2.
(C) −3, 3, −3, 3... Not an AP. The differences are \(+6, -6, +6\), which change from term to term.
(D) 21, 18, 15... An AP. Each term is 3 less than the one before: common difference −3 (a common difference can be negative).