Paint is sold is different sizes. A standard pot is 2.5 litres. This is enough to cover 32m², that is 32 square metres. We will use special one-coat emulsion paint.
So, we need to work out the area of the walls to find out how many pots of paint we will need for bedroom 2. This time it is worth working out the area of the doors and windows. Let's do that first:
I'll do the calculation for the door frame and leave you to do the windows.
The doorframes are 3' x 6'9".

3' is 3 x 12 = 36 inches
That's 36 x 25.4 = 914.4mm
Which is 914.4 ÷ 1000 = 0.9144m
Roughly 0.91m

6'9" is 6 x 12 = 72, plus the extra 9 makes 81 inches
That's 81 x 25.4 = 2057.4mm
Which is 2057.4 ÷ 1000 = 2.0574m
Roughly 2.1m

So, the area for the whole doorframe is:
0.91 x 2.1 = 1.91m²

Now you work out the area of the window.
Don't forget the windows are 5' x 4'.
Round your answers as I did for the doorframe.

Now we can go on to work out the area of the walls.
Again I will show you how to do it with bedroom 2.

Don't forget that the walls are 3m high.

The total length of all of the walls is:
2.5 + 3.1 + 2.5 + 3.1 = 11.2m

So, the area of the walls is: 11.2 x 3 = 33.6m²

There is 1 window (1.8m²) and 1 door (1.91m²). So, the total area to be painted is: 33.6 - 1.8 - 1.91 = 29.89m². Remember that each 2.5 litre tin covers 32m² So, we are lucky and need just less than 1 tin. Better be careful and not spill any!

Now you should work out the total wall area for bedroom 1. Work out the area exactly (don't round your answers). Write down the area, then say how many tins you will need. Don't forget to take away the area of the door and windows.