Sally can paint 3 houses in 12 hours.
John can paint 2 houses in 12 hours.
Together they can paint 5 houses in 12 hours.
12/5 = 2.4 hours per house
John can paint 2 houses in 12 hours.
Together they can paint 5 houses in 12 hours.
12/5 = 2.4 hours per house
John paints house in 6 hrs or one in .166hrs
If they worked together .25+.166= .416 house per hour or,
1/.416= 2.4 hrs per house
First, you need to calculate their individual work rates. Sally can paint the house in 4 hours, so her work rate is 1/4 of the house per hour. Similarly, John's work rate is 1/6 of the house per hour because he can paint it in 6 hours.
To find their combined work rate, you add their individual work rates together. In this case, Sally's work rate is 1/4 and John's work rate is 1/6. So, their combined work rate is 1/4 + 1/6.
To simplify this fraction, you need to find a common denominator, which in this case is 12. Multiply 1/4 by 3/3 (which is equivalent to 1) to get 3/12. Multiply 1/6 by 2/2 to get 2/12.
Now, you can add the fractions together, so 3/12 + 2/12 equals 5/12.
This means that together, Sally and John can paint 5/12 of the house per hour.
To find out how long it will take them to paint the entire house, you can divide 1 by their combined work rate of 5/12.
Dividing 1 by 5/12 is the same as multiplying 1 by the reciprocal of 5/12, which is 12/5.
Therefore, it will take Sally and John (together) 12/5 hours to paint the house. This can also be written as 2.4 hours or 2 hours and 24 minutes.