Subtract 56/7 from 28/21
1st number: 1 7/21, 2nd number: 8 0/7
28/21 - 56/7 is -20/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
28/21 = 28 × 1/21 × 1 = 28/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
56/7 = 56 × 3/7 × 3 = 168/21 - Subtract the two like fractions:
28/21 - 168/21 = 28 - 168/21 = -140/21 - After reducing the fraction, the answer is -20/3
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