Subtract 2/42 from 9/40
9/40 - 2/42 is 149/840.
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,
9/40 = 9 × 21/40 × 21 = 189/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
2/42 = 2 × 20/42 × 20 = 40/840 - Subtract the two like fractions:
189/840 - 40/840 = 189 - 40/840 = 149/840
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/40-2/42 9/40-4/42 9/80-2/42 9/40-2/84 27/40-2/42 9/40-6/42 45/40-2/42 9/40-10/42 63/40-2/42 9/40-14/42