Subtract 21/84 from 18/15
1st number: 1 3/15, 2nd number: 21/84
18/15 - 21/84 is 19/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 15 × 28 = 420,
18/15 = 18 × 28/15 × 28 = 504/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
504/420 - 105/420 = 504 - 105/420 = 399/420 - After reducing the fraction, the answer is 19/20
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