Subtract 21/16 from 18/15
1st number: 1 3/15, 2nd number: 1 5/16
18/15 - 21/16 is -9/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 16 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 15 × 16 = 240,
18/15 = 18 × 16/15 × 16 = 288/240 - Likewise, for the 2nd fraction, since 16 × 15 = 240,
21/16 = 21 × 15/16 × 15 = 315/240 - Subtract the two like fractions:
288/240 - 315/240 = 288 - 315/240 = -27/240 - After reducing the fraction, the answer is -9/80
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