If sally can paint a house in 4 hours and john can paint same house in 6 hours how long would it take both to?

1 / (1/4+1/6) = 2.4 hours = 2hours 24minsIf sally can paint a house in 4 hours and john can paint same house in 6 hours how long would it take both to?
No. of hours to paint together鈥攛:


x/4 + x/6 = 1


3x + 2x = 12


5x = 12


x = 12/5 or 2.4 hours





Answer: 2.4 hours OR 2 hours 24 minutes





Proof (1 job for 2.4 hours painting together):


= 2.4 hours(1/4 + 1/6 rate)


= 2.4 hours(3/12 + 2/12 rate)


= 2.4 hours(5/12 rate)


= 12/12 or 1 jobIf sally can paint a house in 4 hours and john can paint same house in 6 hours how long would it take both to?
Fastest way bis to take product over sum. Thus


4*6/(4+6) = 24/10 = 2.4 hours
5 Hours


6+4=10/2=5