Subtract 20/21 from 8/10
8/10 - 20/21 is -16/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
8/10 = 8 × 21/10 × 21 = 168/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Subtract the two like fractions:
168/210 - 200/210 = 168 - 200/210 = -32/210 - After reducing the fraction, the answer is -16/105
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