Subtract 70/20 from 15/42
1st number: 15/42, 2nd number: 3 10/20
15/42 - 70/20 is -22/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
15/42 = 15 × 10/42 × 10 = 150/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420 - Subtract the two like fractions:
150/420 - 1470/420 = 150 - 1470/420 = -1320/420 - After reducing the fraction, the answer is -22/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/42-70/20 15/84-70/20 15/42-70/40 45/42-70/20 15/42-70/60 75/42-70/20