Subtract 42/16 from 21/84
1st number: 21/84, 2nd number: 2 10/16
21/84 - 42/16 is -19/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 84 × 4 = 336,
21/84 = 21 × 4/84 × 4 = 84/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
42/16 = 42 × 21/16 × 21 = 882/336 - Subtract the two like fractions:
84/336 - 882/336 = 84 - 882/336 = -798/336 - After reducing the fraction, the answer is -19/8
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