Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 12/21 of 15/81?"
1221 × 1581 is 20189.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21×15/81 12/21×30/81 12/42×15/81 36/21×15/81 12/21×45/81 12/63×15/81 60/21×15/81 12/21×75/81 84/21×15/81
© everydaycalculation.com