Subtract 27/42 from 4/40
4/40 - 27/42 is -19/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
27/42 = 27 × 20/42 × 20 = 540/840 - Subtract the two like fractions:
84/840 - 540/840 = 84 - 540/840 = -456/840 - After reducing the fraction, the answer is -19/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/40-27/42 4/40-54/42 4/80-27/42 4/40-27/84 12/40-27/42 4/40-81/42 20/40-27/42 28/40-27/42