Subtract 70/21 from 30/84
1st number: 30/84, 2nd number: 3 7/21
30/84 - 70/21 is -125/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
30/84 = 30 × 1/84 × 1 = 30/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Subtract the two like fractions:
30/84 - 280/84 = 30 - 280/84 = -250/84 - After reducing the fraction, the answer is -125/42
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