Subtract 16/21 from 8/18
8/18 - 16/21 is -20/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
16/21 = 16 × 6/21 × 6 = 96/126 - Subtract the two like fractions:
56/126 - 96/126 = 56 - 96/126 = -40/126 - After reducing the fraction, the answer is -20/63
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