Subtract 45/40 from 12/20
1st number: 12/20, 2nd number: 1 5/40
12/20 - 45/40 is -21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
12/20 = 12 × 2/20 × 2 = 24/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
45/40 = 45 × 1/40 × 1 = 45/40 - Subtract the two like fractions:
24/40 - 45/40 = 24 - 45/40 = -21/40
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