Solutions by everydaycalculation.com
1290 - 3090 is -15.
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/90-30/90 12/90-60/90 36/90-30/90 60/90-30/90 84/90-30/90
© everydaycalculation.com