Subtract 21/70 from 18/56
18/56 - 21/70 is 3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
18/56 = 18 × 5/56 × 5 = 90/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Subtract the two like fractions:
90/280 - 84/280 = 90 - 84/280 = 6/280 - After reducing the fraction, the answer is 3/140
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