Posted by Richard on Thursday, March 22, 2012 at 12:40pm.
14 metres of rope costs €9.52. If Joe bought 21 metres, how much change out of €20.00 do Joe get? Is there a shorter way of doing this other than dividing, multiplying and then subtracting?

Maths  PsyDAG, Friday, March 23, 2012 at 5:28pm
Not that I know about.