Subtract 90/21 from 18/60
1st number: 18/60, 2nd number: 4 6/21
18/60 - 90/21 is -279/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
18/60 = 18 × 7/60 × 7 = 126/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Subtract the two like fractions:
126/420 - 1800/420 = 126 - 1800/420 = -1674/420 - After reducing the fraction, the answer is -279/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/60-90/21 18/60-90/42 54/60-90/21 18/60-90/63 90/60-90/21