Subtract 42/28 from 28/21
1st number: 1 7/21, 2nd number: 1 14/28
28/21 - 42/28 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
42/28 = 42 × 3/28 × 3 = 126/84 - Subtract the two like fractions:
112/84 - 126/84 = 112 - 126/84 = -14/84 - After reducing the fraction, the answer is -1/6
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