Subtract 18/20 from 21/24
21/24 - 18/20 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 20 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120 - Likewise, for the 2nd fraction, since 20 × 6 = 120,
18/20 = 18 × 6/20 × 6 = 108/120 - Subtract the two like fractions:
105/120 - 108/120 = 105 - 108/120 = -3/120 - After reducing the fraction, the answer is -1/40
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