Find the wrong number in the sequence : 52, 51, 48, 43, 34, 27, 16
2010
Find the wrong number in the sequence :
52, 51, 48, 43, 34, 27, 16
Answer: B. 34 — CONCEPT In a difference-based number series, compare each pair of consecutive terms. A regular pattern in the differences reveals the governing rule. When the…
- A.
27
- B.
34
- C.
43
- D.
48
Attempted by 5 students.
Show answer & explanation
Correct answer: B
CONCEPT
In a difference-based number series, compare each pair of consecutive terms. A regular pattern in the differences reveals the governing rule.
When the differences are consecutive odd numbers, the sequence subtracts 1, 3, 5, 7, 9, 11, and so on.
APPLICATION
52 − 1 = 51.
51 − 3 = 48.
48 − 5 = 43.
43 − 7 = 36; therefore the fifth term should be 36.
36 − 9 = 27.
27 − 11 = 16.
CROSS-CHECK
Replacing 34 with 36 gives the differences −1, −3, −5, −7, −9, and −11, which are consecutive negative odd numbers.
Hence, 34 is the wrong number in the displayed sequence.