Subtract 7/21 from 42/40
1st number: 1 2/40, 2nd number: 7/21
42/40 - 7/21 is 43/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
7/21 = 7 × 40/21 × 40 = 280/840 - Subtract the two like fractions:
882/840 - 280/840 = 882 - 280/840 = 602/840 - After reducing the fraction, the answer is 43/60
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/40-7/21 42/40-14/21 42/80-7/21 42/40-7/42 42/40-7/63 42/40-35/21 42/40-49/21