Subtract 40/84 from 18/21
18/21 - 40/84 is 8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Subtract the two like fractions:
72/84 - 40/84 = 72 - 40/84 = 32/84 - After reducing the fraction, the answer is 8/21
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