Subtract 54/8 from 21/30
1st number: 21/30, 2nd number: 6 6/8
21/30 - 54/8 is -121/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
54/8 = 54 × 15/8 × 15 = 810/120 - Subtract the two like fractions:
84/120 - 810/120 = 84 - 810/120 = -726/120 - After reducing the fraction, the answer is -121/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30-54/8 21/60-54/8 21/30-54/16 63/30-54/8 21/90-54/8 21/30-54/24 21/30-54/40 21/30-54/56