Subtract 21/8 from 25/90
1st number: 25/90, 2nd number: 2 5/8
25/90 - 21/8 is -169/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
25/90 = 25 × 4/90 × 4 = 100/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Subtract the two like fractions:
100/360 - 945/360 = 100 - 945/360 = -845/360 - After reducing the fraction, the answer is -169/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/90-21/8 25/90-42/8 25/90-21/16 75/90-21/8 25/90-63/8 25/90-21/24 25/90-21/40 25/90-21/56