Subtract 21/30 from 9/90
9/90 - 21/30 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
9/90 = 9 × 1/90 × 1 = 9/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Subtract the two like fractions:
9/90 - 63/90 = 9 - 63/90 = -54/90 - After reducing the fraction, the answer is -3/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/90-21/30 9/90-42/30 9/90-21/60 27/90-21/30 9/90-63/30 9/90-21/90 45/90-21/30 63/90-21/30