Subtract 21/24 from 28/40
28/40 - 21/24 is -7/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 24 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
28/40 = 28 × 3/40 × 3 = 84/120 - Likewise, for the 2nd fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120 - Subtract the two like fractions:
84/120 - 105/120 = 84 - 105/120 = -21/120 - After reducing the fraction, the answer is -7/40
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