Subtract 42/27 from 21/70
1st number: 21/70, 2nd number: 1 15/27
21/70 - 42/27 is -113/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 27 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 70 × 27 = 1890,
21/70 = 21 × 27/70 × 27 = 567/1890 - Likewise, for the 2nd fraction, since 27 × 70 = 1890,
42/27 = 42 × 70/27 × 70 = 2940/1890 - Subtract the two like fractions:
567/1890 - 2940/1890 = 567 - 2940/1890 = -2373/1890 - After reducing the fraction, the answer is -113/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/70-42/27 21/70-84/27 21/70-42/54 63/70-42/27 21/70-42/81