Subtract 21/12 from 42/48
1st number: 42/48, 2nd number: 1 9/12
42/48 - 21/12 is -7/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 48 and 12 is 48
Next, find the equivalent fraction of both fractional numbers with denominator 48 - For the 1st fraction, since 48 × 1 = 48,
42/48 = 42 × 1/48 × 1 = 42/48 - Likewise, for the 2nd fraction, since 12 × 4 = 48,
21/12 = 21 × 4/12 × 4 = 84/48 - Subtract the two like fractions:
42/48 - 84/48 = 42 - 84/48 = -42/48 - After reducing the fraction, the answer is -7/8
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