Subtract 84/8 from 10/21
1st number: 10/21, 2nd number: 10 4/8
10/21 - 84/8 is -421/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
10/21 = 10 × 8/21 × 8 = 80/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
84/8 = 84 × 21/8 × 21 = 1764/168 - Subtract the two like fractions:
80/168 - 1764/168 = 80 - 1764/168 = -1684/168 - After reducing the fraction, the answer is -421/42
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