Subtract 3/90 from 7/40
7/40 - 3/90 is 17/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
7/40 = 7 × 9/40 × 9 = 63/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
3/90 = 3 × 4/90 × 4 = 12/360 - Subtract the two like fractions:
63/360 - 12/360 = 63 - 12/360 = 51/360 - After reducing the fraction, the answer is 17/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/40-3/90 7/40-6/90 7/80-3/90 21/40-3/90 7/40-9/90 35/40-3/90 7/40-15/90 49/40-3/90 7/40-21/90