Subtract 42/16 from 21/12
1st number: 1 9/12, 2nd number: 2 10/16
21/12 - 42/16 is -7/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 16 is 48
Next, find the equivalent fraction of both fractional numbers with denominator 48 - For the 1st fraction, since 12 × 4 = 48,
21/12 = 21 × 4/12 × 4 = 84/48 - Likewise, for the 2nd fraction, since 16 × 3 = 48,
42/16 = 42 × 3/16 × 3 = 126/48 - Subtract the two like fractions:
84/48 - 126/48 = 84 - 126/48 = -42/48 - After reducing the fraction, the answer is -7/8
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