Subtract 45/30 from 81/84
1st number: 81/84, 2nd number: 1 15/30
81/84 - 45/30 is -15/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
45/30 = 45 × 14/30 × 14 = 630/420 - Subtract the two like fractions:
405/420 - 630/420 = 405 - 630/420 = -225/420 - After reducing the fraction, the answer is -15/28
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