Subtract 42/8 from 21/18
1st number: 1 3/18, 2nd number: 5 2/8
21/18 - 42/8 is -49/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
42/8 = 42 × 9/8 × 9 = 378/72 - Subtract the two like fractions:
84/72 - 378/72 = 84 - 378/72 = -294/72 - After reducing the fraction, the answer is -49/12
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