Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 5/21 of 6/40?"
521 × 640 is 128.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/21×6/40 5/21×12/40 5/42×6/40 5/21×6/80 15/21×6/40 5/21×18/40 5/63×6/40 25/21×6/40 5/21×30/40 35/21×6/40 5/21×42/40
© everydaycalculation.com