Subtract 63/28 from 21/42
1st number: 21/42, 2nd number: 2 7/28
21/42 - 63/28 is -7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
63/28 = 63 × 3/28 × 3 = 189/84 - Subtract the two like fractions:
42/84 - 189/84 = 42 - 189/84 = -147/84 - After reducing the fraction, the answer is -7/4
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