Subtract 81/21 from 24/70
1st number: 24/70, 2nd number: 3 18/21
24/70 - 81/21 is -123/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
24/70 = 24 × 3/70 × 3 = 72/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
81/21 = 81 × 10/21 × 10 = 810/210 - Subtract the two like fractions:
72/210 - 810/210 = 72 - 810/210 = -738/210 - After reducing the fraction, the answer is -123/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 48/70-81/21 24/70-81/42 72/70-81/21 24/70-81/63