Subtract 21/42 from 72/4
1st number: 18 0/4, 2nd number: 21/42
72/4 - 21/42 is 35/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
72/4 = 72 × 21/4 × 21 = 1512/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Subtract the two like fractions:
1512/84 - 42/84 = 1512 - 42/84 = 1470/84 - After reducing the fraction, the answer is 35/2
- In mixed form: 171/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/8-21/42 72/4-21/84 72/4-63/42 72/12-21/42 72/20-21/42 72/28-21/42