Subtract 60/40 from 21/42
1st number: 21/42, 2nd number: 1 20/40
21/42 - 60/40 is -1/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
21/42 = 21 × 20/42 × 20 = 420/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
60/40 = 60 × 21/40 × 21 = 1260/840 - Subtract the two like fractions:
420/840 - 1260/840 = 420 - 1260/840 = -840/840 - After reducing the fraction, the answer is -1/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/84-60/40 21/42-60/80 63/42-60/40