Subtract 21/7 from 18/15
1st number: 1 3/15, 2nd number: 3 0/7
18/15 - 21/7 is -9/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
18/15 = 18 × 7/15 × 7 = 126/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
21/7 = 21 × 15/7 × 15 = 315/105 - Subtract the two like fractions:
126/105 - 315/105 = 126 - 315/105 = -189/105 - After reducing the fraction, the answer is -9/5
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