Subtract 30/72 from 21/2
1st number: 10 1/2, 2nd number: 30/72
21/2 - 30/72 is 121/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 2 × 36 = 72,
21/2 = 21 × 36/2 × 36 = 756/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
30/72 = 30 × 1/72 × 1 = 30/72 - Subtract the two like fractions:
756/72 - 30/72 = 756 - 30/72 = 726/72 - After reducing the fraction, the answer is 121/12
- In mixed form: 101/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/2-30/72 21/2-60/72 21/4-30/72 63/2-30/72 21/2-90/72 21/6-30/72 21/10-30/72 21/14-30/72