Subtract 42/80 from 28/42
28/42 - 42/80 is 17/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
28/42 = 28 × 40/42 × 40 = 1120/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Subtract the two like fractions:
1120/1680 - 882/1680 = 1120 - 882/1680 = 238/1680 - After reducing the fraction, the answer is 17/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/42-42/80 28/42-84/80 28/84-42/80 84/42-42/80