Subtract 81/4 from 42/18
1st number: 2 6/18, 2nd number: 20 1/4
42/18 - 81/4 is -215/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 4 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
42/18 = 42 × 2/18 × 2 = 84/36 - Likewise, for the 2nd fraction, since 4 × 9 = 36,
81/4 = 81 × 9/4 × 9 = 729/36 - Subtract the two like fractions:
84/36 - 729/36 = 84 - 729/36 = -645/36 - After reducing the fraction, the answer is -215/12
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