Subtract 21/40 from 1/3
1/3 - 21/40 is -23/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 3 × 40 = 120,
1/3 = 1 × 40/3 × 40 = 40/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
40/120 - 63/120 = 40 - 63/120 = -23/120
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