Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 20/40 of 21/30?"
2040 × 2130 is 720.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/40×42/30 20/80×21/30 20/40×21/60 60/40×21/30 20/40×63/30 20/40×21/90
© everydaycalculation.com