http://www.aaa3.net/how-to-scale-floor-plans/

need help with this on homework?
A playroom is 12 ft wide. How wide is it on a floor plan drawn to the scale 1 in. = 10 ft?
1.2 in
I am nearly positive this is right. And i am studying additional maths.
Hope this helps.
Feng Shui – Why you need to Draw a Floor Plan To Scale here