Subtract 28/21 from 3/15
1st number: 3/15, 2nd number: 1 7/21
3/15 - 28/21 is -17/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
3/15 = 3 × 7/15 × 7 = 21/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Subtract the two like fractions:
21/105 - 140/105 = 21 - 140/105 = -119/105 - After reducing the fraction, the answer is -17/15
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