Subtract 18/21 from 7/8
7/8 - 18/21 is 1/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
7/8 = 7 × 21/8 × 21 = 147/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168 - Subtract the two like fractions:
147/168 - 144/168 = 147 - 144/168 = 3/168 - After reducing the fraction, the answer is 1/56
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