Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 15/21 of 21/30?"
1521 × 2130 is 12.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21×21/30 15/21×42/30 15/42×21/30 15/21×21/60 45/21×21/30 15/21×63/30 15/63×21/30 15/21×21/90 75/21×21/30
© everydaycalculation.com