Subtract 70/54 from 20/21
1st number: 20/21, 2nd number: 1 16/54
20/21 - 70/54 is -65/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
20/21 = 20 × 18/21 × 18 = 360/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
70/54 = 70 × 7/54 × 7 = 490/378 - Subtract the two like fractions:
360/378 - 490/378 = 360 - 490/378 = -130/378 - After reducing the fraction, the answer is -65/189
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