Subtract 49/70 from 12/90
12/90 - 49/70 is -17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
49/70 = 49 × 9/70 × 9 = 441/630 - Subtract the two like fractions:
84/630 - 441/630 = 84 - 441/630 = -357/630 - After reducing the fraction, the answer is -17/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/90-49/70 12/90-98/70 36/90-49/70 60/90-49/70 84/90-49/70