Subtract 42/9 from 27/7
1st number: 3 6/7, 2nd number: 4 6/9
27/7 - 42/9 is -17/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
27/7 = 27 × 9/7 × 9 = 243/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
42/9 = 42 × 7/9 × 7 = 294/63 - Subtract the two like fractions:
243/63 - 294/63 = 243 - 294/63 = -51/63 - After reducing the fraction, the answer is -17/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/7-42/9 27/7-84/9 27/14-42/9 27/7-42/18 81/7-42/9 27/21-42/9 27/7-42/27 27/35-42/9 27/7-42/45 27/49-42/9 27/7-42/63