Subtract 40/21 from 4/15
1st number: 4/15, 2nd number: 1 19/21
4/15 - 40/21 is -172/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
4/15 = 4 × 7/15 × 7 = 28/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
40/21 = 40 × 5/21 × 5 = 200/105 - Subtract the two like fractions:
28/105 - 200/105 = 28 - 200/105 = -172/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/15-40/21 4/15-80/21 4/30-40/21 4/15-40/42 12/15-40/21 4/45-40/21 4/15-40/63 20/15-40/21 4/75-40/21 28/15-40/21