Subtract 45/80 from 8/21
8/21 - 45/80 is -61/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
8/21 = 8 × 80/21 × 80 = 640/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
45/80 = 45 × 21/80 × 21 = 945/1680 - Subtract the two like fractions:
640/1680 - 945/1680 = 640 - 945/1680 = -305/1680 - After reducing the fraction, the answer is -61/336
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/21-45/80 8/21-90/80 8/42-45/80 24/21-45/80 8/63-45/80 40/21-45/80 56/21-45/80