Subtract 7/16 from 21/90
21/90 - 7/16 is -49/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 16 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 16 × 45 = 720,
7/16 = 7 × 45/16 × 45 = 315/720 - Subtract the two like fractions:
168/720 - 315/720 = 168 - 315/720 = -147/720 - After reducing the fraction, the answer is -49/240
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/90-7/16 21/90-14/16 21/90-7/32 63/90-7/16 21/90-21/16 21/90-7/48 21/90-35/16 21/90-7/80 21/90-49/16