Subtract 90/84 from 21/30
1st number: 21/30, 2nd number: 1 6/84
21/30 - 90/84 is -13/35.
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,
21/30 = 21 × 14/30 × 14 = 294/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420 - Subtract the two like fractions:
294/420 - 450/420 = 294 - 450/420 = -156/420 - After reducing the fraction, the answer is -13/35
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