Subtract 5/10 from 8/21
8/21 - 5/10 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
8/21 = 8 × 10/21 × 10 = 80/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
5/10 = 5 × 21/10 × 21 = 105/210 - Subtract the two like fractions:
80/210 - 105/210 = 80 - 105/210 = -25/210 - After reducing the fraction, the answer is -5/42
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