Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 21/42 of 63/81?"
2142 × 6381 is 718.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/84×63/81 63/42×63/81
© everydaycalculation.com