Subtract 90/72 from 45/50
1st number: 45/50, 2nd number: 1 18/72
45/50 - 90/72 is -7/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 72 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 50 × 36 = 1800,
45/50 = 45 × 36/50 × 36 = 1620/1800 - Likewise, for the 2nd fraction, since 72 × 25 = 1800,
90/72 = 90 × 25/72 × 25 = 2250/1800 - Subtract the two like fractions:
1620/1800 - 2250/1800 = 1620 - 2250/1800 = -630/1800 - After reducing the fraction, the answer is -7/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/50-90/72