Subtract 15/20 from 90/84
1st number: 1 6/84, 2nd number: 15/20
90/84 - 15/20 is 9/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
15/20 = 15 × 21/20 × 21 = 315/420 - Subtract the two like fractions:
450/420 - 315/420 = 450 - 315/420 = 135/420 - After reducing the fraction, the answer is 9/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/84-30/20 90/84-15/40 90/84-45/20 90/84-15/60 90/84-75/20