Subtract 9/90 from 3/72
3/72 - 9/90 is -7/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
3/72 = 3 × 5/72 × 5 = 15/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
9/90 = 9 × 4/90 × 4 = 36/360 - Subtract the two like fractions:
15/360 - 36/360 = 15 - 36/360 = -21/360 - After reducing the fraction, the answer is -7/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/72-9/90 3/72-18/90 9/72-9/90 3/72-27/90 15/72-9/90 3/72-45/90 21/72-9/90 3/72-63/90