Subtract 28/10 from 21/84
1st number: 21/84, 2nd number: 2 8/10
21/84 - 28/10 is -51/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 10 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 10 × 42 = 420,
28/10 = 28 × 42/10 × 42 = 1176/420 - Subtract the two like fractions:
105/420 - 1176/420 = 105 - 1176/420 = -1071/420 - After reducing the fraction, the answer is -51/20
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