Question

How many ‘5’ s are there which are followed by ‘0’ and preceded by ‘0’ in the following series 1570507005125050050

• A. 1
• B. 5
• C. 4
• D. 3

Answer 1

Answer:

D. 3

In the given series, we need to find how many 5s are placed exactly between two 0s (forming the pattern 050). The Series: 1 5 7 0 5 0 7 0 0 5 1 2 5 0 5 0 0 5 0 1. 1 5 7 [0 5 0] 7... (First occurrence) 2. ...7 0 0 5 1 2 5 [0 5 0] ... (Second occurrence) 3. ...0 5 0 [0 5 0] (Third occurrence - the zero at the end of the previous 050 acts as the start of this one). Actually, let's look closer at the string: 1570507005125050050 * 1 5 7 (0 5 0) 7 -> 1 * 7 0 0 5 1 2 5 (0 5 0) -> 2 * 5 0 5 0 (0 5 0) -> 3 Final Answer: There are 3 such 5s in the series.