Subtract 70/21 from 28/42
1st number: 28/42, 2nd number: 3 7/21
28/42 - 70/21 is -8/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42 - Subtract the two like fractions:
28/42 - 140/42 = 28 - 140/42 = -112/42 - After reducing the fraction, the answer is -8/3
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