Subtract 21/56 from 18/30
18/30 - 21/56 is 9/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 30 × 28 = 840,
18/30 = 18 × 28/30 × 28 = 504/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
21/56 = 21 × 15/56 × 15 = 315/840 - Subtract the two like fractions:
504/840 - 315/840 = 504 - 315/840 = 189/840 - After reducing the fraction, the answer is 9/40
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