Question

Refer to the following number series and answer the question that follows.

4 3 9 1 5 3 9 2 4 3 5 9 5 7 9 2 6 8 7

How many such odd digits are there, each of which is immediately preceded by an even digit and also immediately followed by an odd digit?

• A. One
• B. Four
• C. Two
• D. Three

Answer 1

Answer:

C. Two

There are 2 odd digits that are immediately preceded by an even digit and also immediately followed by an odd digit.

We need to find groups that fit the pattern: Even Digit $\rightarrow$ Odd Digit (Target) $\rightarrow$ Odd Digit

(Even digits are 2, 4, 6, 8. Odd digits are 1, 3, 5, 7, 9.)

1. 4 3 9 $\rightarrow$ Match 1: The odd digit 3 is preceded by even 4 and followed by odd 9.

2. 3 9 1 $\rightarrow$ No (preceded by odd 3).

3. 9 1 5 $\rightarrow$ No (preceded by odd 9).

4. 1 5 3 $\rightarrow$ No (preceded by odd 1).

5. 5 3 9 $\rightarrow$ No (preceded by odd 5).

6. 3 9 2 $\rightarrow$ No (followed by even 2).

7. 9 2 4 $\rightarrow$ No.

8. 2 4 3 $\rightarrow$ No (followed by even 4).

9. 4 3 5 $\rightarrow$ Match 2: The odd digit 3 is preceded by even 4 and followed by odd 5.

10. 3 5 9 $\rightarrow$ No (preceded by odd 3).

11. 5 9 5 $\rightarrow$ No (preceded by odd 5).

12. 9 5 7 $\rightarrow$ No (preceded by odd 9).

13. 5 7 9 $\rightarrow$ No (preceded by odd 5).

14. 7 9 2 $\rightarrow$ No (followed by even 2).

15. 9 2 6 $\rightarrow$ No.

16. 2 6 8 $\rightarrow$ No.

17. 6 8 7 $\rightarrow$ No (followed by nothing).