This is the concept of proportionality, we are required to calculate for the number of hours two crews can use to paint the house altogether.
Here proceed as follows;
number of hours new crew can paint=12 hrs
portion of work painted by new crew in 1 hour= 1/12
number of hours experienced crew can paint=6 hours
Portion of work painted by experienced crew in 1 hour=1/6
Portion of work painted by the two crews altogether in 1 hour will be:
1/6+1/12=1/4
thus the total amount of hours that the two painters will take to paint will be:
4 hours
21/7=3mins per wall with 5 people.
Because we assume that all of the people paint at the same rate, 3 X 5=15 mins for one person working alone.
15/3=5 mins per wall with 3 people X 10 people= 50 mins for 3 people to paint 10 walls.
The answer is 50 mins.
Answer:
-1/3 - (-5/12) = 1/12.
Step-by-step explanation:
Simpler equation:
6/12 + (-5/12) = 1/12
Or This:
6/12 - 5/12 = 1/12.
hope this helped.