Subtract 1/90 from 30/72
30/72 - 1/90 is 73/180.
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,
30/72 = 30 × 5/72 × 5 = 150/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
1/90 = 1 × 4/90 × 4 = 4/360 - Subtract the two like fractions:
150/360 - 4/360 = 150 - 4/360 = 146/360 - After reducing the fraction, the answer is 73/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/72-1/90 30/72-2/90 90/72-1/90 30/72-3/90 30/72-5/90 30/72-7/90