Subtract 21/20 from 18/40
1st number: 18/40, 2nd number: 1 1/20
18/40 - 21/20 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
18/40 = 18 × 1/40 × 1 = 18/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
21/20 = 21 × 2/20 × 2 = 42/40 - Subtract the two like fractions:
18/40 - 42/40 = 18 - 42/40 = -24/40 - After reducing the fraction, the answer is -3/5
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