Subtract 21/12 from 25/40
1st number: 25/40, 2nd number: 1 9/12
25/40 - 21/12 is -9/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
25/40 = 25 × 3/40 × 3 = 75/120 - Likewise, for the 2nd fraction, since 12 × 10 = 120,
21/12 = 21 × 10/12 × 10 = 210/120 - Subtract the two like fractions:
75/120 - 210/120 = 75 - 210/120 = -135/120 - After reducing the fraction, the answer is -9/8
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