Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 16/21 of 20/40?"
1621 × 2040 is 821.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 32/21×20/40 16/42×20/40 16/21×20/80 48/21×20/40 16/21×60/40 16/63×20/40 80/21×20/40
© everydaycalculation.com