Subtract 21/15 from 12/16
1st number: 12/16, 2nd number: 1 6/15
12/16 - 21/15 is -13/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 15 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 16 × 15 = 240,
12/16 = 12 × 15/16 × 15 = 180/240 - Likewise, for the 2nd fraction, since 15 × 16 = 240,
21/15 = 21 × 16/15 × 16 = 336/240 - Subtract the two like fractions:
180/240 - 336/240 = 180 - 336/240 = -156/240 - After reducing the fraction, the answer is -13/20
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