Solutions by everydaycalculation.com
This multiplication involving fractions can also be rephrased as "What is 40/70 of 40/90?"
4070 × 4090 is 1663.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/70×40/90 40/70×80/90
© everydaycalculation.com