Subtract 21/40 from 40/21
1st number: 1 19/21, 2nd number: 21/40
40/21 - 21/40 is 1159/840.
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,
40/21 = 40 × 40/21 × 40 = 1600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Subtract the two like fractions:
1600/840 - 441/840 = 1600 - 441/840 = 1159/840 - In mixed form: 1319/840
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