Subtract 21/90 from 16/45
16/45 - 21/90 is 11/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
16/45 = 16 × 2/45 × 2 = 32/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
32/90 - 21/90 = 32 - 21/90 = 11/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 32/45-21/90 16/45-42/90 16/90-21/90 48/45-21/90 16/45-63/90 80/45-21/90