Question
Download Solution PDFA device needs 4 batteries to run. Each battery runs for 2 days. If there are a total of 6 batteries available, what is the maximum number of days for which the device can be run by strategically replacing the batteries till all the batteries are completely drained of power?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFExplanation:
Total batteries = 6
Each battery runs for 2 days
So total time cover by all batteries = 6 × 2 = 12
Now, we need 4 batteries to run the device
So required maximum number of days = 12/4 = 3
Option (2) is correct.
Alternate Method Let 6 batteries are P, Q, R, S, T, U
Possible pair of 4 batteries where all batteries will run for two days = PQRS, PQTU, RSTU
So maximum number of days = 3
Option (2) is correct
Last updated on Jun 5, 2025
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