Subtract 90/84 from 18/30
1st number: 18/30, 2nd number: 1 6/84
18/30 - 90/84 is -33/70.
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,
18/30 = 18 × 14/30 × 14 = 252/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420 - Subtract the two like fractions:
252/420 - 450/420 = 252 - 450/420 = -198/420 - After reducing the fraction, the answer is -33/70
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