Subtract 81/84 from 7/30
7/30 - 81/84 is -307/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
7/30 = 7 × 14/30 × 14 = 98/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Subtract the two like fractions:
98/420 - 405/420 = 98 - 405/420 = -307/420
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