Answer:
2hrs 24 mins
Explanation:
Ok so let's make this problem a bit simpler by splitting it up.
Tim paints a room in 6 hours.
So, we can also say that she paints 1/6 of that room in 1 hour
Bella paints it in 4 hours
So, we can also say that she paints 1/4 of that room in 1 hour
Now, lets see what we have:
Bella: 1/4 every hour
Tim: 1/6 every hour
The problem states that they are working together, so we need to add the values we have:
1/4 + 1/6
We cannot just add them, we must make them have the same common denominator.
LCD is 12, you can find that by just doing the times tables for 4 and 6 and seeing what number they match on first.
3/12 + 2/12 = 5/12
So, tim and bella working together paint 5/12 of a room in 1 hour.
They paint 5/12 of a room in 60 minutes
They paint 1/12 of the room in 12 minutes(divide both values by 5)
So if they paint 1/12 of the room in 12 minutes, we can multiply both values by 12 to get our answer.
They paint the full room in 144 minutes(12*12).
144 minutes is 2 hours and 24 minutes