Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 40/81 of 21/63?"
4081 × 2163 is 40243.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/81×21/63 40/81×42/63
© everydaycalculation.com