Subtract 18/9 from 21/15
1st number: 1 6/15, 2nd number: 2 0/9
21/15 - 18/9 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 15 × 3 = 45,
21/15 = 21 × 3/15 × 3 = 63/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
18/9 = 18 × 5/9 × 5 = 90/45 - Subtract the two like fractions:
63/45 - 90/45 = 63 - 90/45 = -27/45 - After reducing the fraction, the answer is -3/5
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