Subtract 9/40 from 28/42
28/42 - 9/40 is 53/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
28/42 = 28 × 20/42 × 20 = 560/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840 - Subtract the two like fractions:
560/840 - 189/840 = 560 - 189/840 = 371/840 - After reducing the fraction, the answer is 53/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/42-9/40 28/42-18/40 28/84-9/40 28/42-9/80 84/42-9/40 28/42-27/40 28/42-45/40 28/42-63/40