Discussion
A briefcase has a number-lock system containing a combination of 3 digits (Each digit can be of numbers 0 to 8). If the correct combination is unknown, how much maximum time would be required to open the bag if each “trial” of combination takes 3 seconds?
Answer: B
Each digit runs from 0 to 8, giving nine choices, and repetition is allowed.
\[ 9 \times 9 \times 9 = 729 \text{ combinations} \]
\[ 729 \times 3 = 2187 \text{ seconds} \]
\[ \frac{2187}{60} = 36.45 \text{ minutes} \]
The digits go up to 8, not 9, so it is \( 9^{3} \) and not \( 10^{3} \).
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development