Just multiply the width by the length and divide by 9, which will give you the square yardage (34.2222). Simply multiply that figure by the cost per yard... 554.39 (agreeing with Oldgeezer)
Near enough!!?? Yours is miles out, or should I say pounds? I agree with OG's calculation. You can't just forget the decimals - look how much difference it makes here - £117 that's almost 27% of your £437.40!
In a shop they'd probably round it up to the nearest sq yd, which means they'd charge you £550.80. Whatever you do don't run a business - you'd be bankrupt after the first week.
It is possible to obtain at a reasonable price (£1 in poundland) electronic pocket calculators that can do quite sophisticated calculations.The one I have before me has functions that I had never heard of or am ever likely to need. It agrees exactly with OG, decimals included! I advise you to get one, you will need it if you ever have to do a tax return.
Yes it was a mistake and she meant lounge carpet as I did think it was a bit big! I'm completely new to this as I work on something else. But thanks for the tips. :)