Subtract 28/20 from 90/84
1st number: 1 6/84, 2nd number: 1 8/20
90/84 - 28/20 is -23/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
28/20 = 28 × 21/20 × 21 = 588/420 - Subtract the two like fractions:
450/420 - 588/420 = 450 - 588/420 = -138/420 - After reducing the fraction, the answer is -23/70
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