Solutions by everydaycalculation.com
640 - 540 is 140.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 12/40-5/40 6/40-10/40 6/80-5/40 6/40-5/80 18/40-5/40 6/40-15/40 30/40-5/40 6/40-25/40 42/40-5/40 6/40-35/40
© everydaycalculation.com