Subtract 27/15 from 21/40
1st number: 21/40, 2nd number: 1 12/15
21/40 - 27/15 is -51/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
27/15 = 27 × 8/15 × 8 = 216/120 - Subtract the two like fractions:
63/120 - 216/120 = 63 - 216/120 = -153/120 - After reducing the fraction, the answer is -51/40
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