Subtract 4/70 from 21/56
21/56 - 4/70 is 89/280.
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,
21/56 = 21 × 5/56 × 5 = 105/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
4/70 = 4 × 4/70 × 4 = 16/280 - Subtract the two like fractions:
105/280 - 16/280 = 105 - 16/280 = 89/280
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