Subtract 12/5 from 21/40
1st number: 21/40, 2nd number: 2 2/5
21/40 - 12/5 is -15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 5 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 5 × 8 = 40,
12/5 = 12 × 8/5 × 8 = 96/40 - Subtract the two like fractions:
21/40 - 96/40 = 21 - 96/40 = -75/40 - After reducing the fraction, the answer is -15/8
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