Subtract 3/80 from 21/12
1st number: 1 9/12, 2nd number: 3/80
21/12 - 3/80 is 137/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
21/12 = 21 × 20/12 × 20 = 420/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
3/80 = 3 × 3/80 × 3 = 9/240 - Subtract the two like fractions:
420/240 - 9/240 = 420 - 9/240 = 411/240 - After reducing the fraction, the answer is 137/80
- In mixed form: 157/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12-3/80 21/12-6/80 21/24-3/80 63/12-3/80 21/12-9/80 21/36-3/80 21/12-15/80 21/60-3/80 21/12-21/80 21/84-3/80