Subtract 21/40 from 45/42
1st number: 1 3/42, 2nd number: 21/40
45/42 - 21/40 is 153/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
45/42 = 45 × 20/42 × 20 = 900/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Subtract the two like fractions:
900/840 - 441/840 = 900 - 441/840 = 459/840 - After reducing the fraction, the answer is 153/280
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