Jack can paint a wall in 5 hours and John can paint the same wall in 6 hours. If they work together, how long would it take for both of them to finish the job?
Possible answers: 2h 18min, 2h 44min, 3h 5min, 3h 40min, 4h 6min
My solution:
rate of Jack= 1/5
rate of John=1/6
Total: 1= 1/5t+ 1/6t
t=30/11 which is 2.72 which I think is 3h and 2min
But the answer is 2h and 44min and I'm not sure why
1 answer
To convert 2.72 hours to minutes, we can multiply by 60 to get 163.2 minutes. Rounding to the nearest minute, we get 163 minutes, which is equivalent to 2 hours and 43 minutes. Therefore, the answer of 2 hours and 44 minutes is the closest option to our calculated time of 2.72 hours.
1 answer