Subtract 49/40 from 20/21
1st number: 20/21, 2nd number: 1 9/40
20/21 - 49/40 is -229/840.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
20/21 = 20 × 40/21 × 40 = 800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
49/40 = 49 × 21/40 × 21 = 1029/840 - Subtract the two like fractions:
800/840 - 1029/840 = 800 - 1029/840 = -229/840
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