Subtract 20/8 from 21/54
1st number: 21/54, 2nd number: 2 4/8
21/54 - 20/8 is -19/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 8 is 216
Next, find the equivalent fraction of both fractional numbers with denominator 216 - For the 1st fraction, since 54 × 4 = 216,
21/54 = 21 × 4/54 × 4 = 84/216 - Likewise, for the 2nd fraction, since 8 × 27 = 216,
20/8 = 20 × 27/8 × 27 = 540/216 - Subtract the two like fractions:
84/216 - 540/216 = 84 - 540/216 = -456/216 - After reducing the fraction, the answer is -19/9
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