Solutions by everydaycalculation.com
521 - 121 is 421.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/21-1/21 5/21-2/21 5/42-1/21 5/21-1/42 15/21-1/21 5/21-3/21 5/63-1/21 5/21-1/63 25/21-1/21 5/21-5/21 35/21-1/21 5/21-7/21
© everydaycalculation.com