How many 4’s are there in the following number series which are immediately…
2022
How many 4’s are there in the following number series which are immediately preceded by 8, but not immediately followed by 9? Number series: 1 4 9 3 4 5 8 4 9 3 8 4 6 7 8 4 5 2 6 4 9 1 3 1 6 8 4 7
- A.
4
- B.
3
- C.
2
- D.
1
Attempted by 150 students.
Show answer & explanation
Correct answer: B
Method: scan the series left to right and identify each 4 that has an 8 immediately before it and a number other than 9 immediately after it.
8 4 6 — counts (preceded by 8, followed by 6)
8 4 5 — counts (preceded by 8, followed by 5)
8 4 7 — counts (preceded by 8, followed by 7)
Note: There is another 4 that follows an 8 (the segment "8 4 9"), but it must be excluded because it is immediately followed by 9.
Answer: 3