Correct option is B
Given:
- Each battery lasts 2 days.
- The device needs 4 batteries to run.
- Total batteries = 6.
Formula:
Maximum runtime = Total battery-days ÷ 4 (number of batteries used at once).
Solution:
- Each battery lasts for 2 days, so total battery-days:
6 × 2 = 12 battery-days - Divide the total battery-days by the number of batteries required at once:
Maximum runtime = 12 ÷ 4 = 3 days
Final Answer: (b) 3


