Subtract 4/6 from 21/40
21/40 - 4/6 is -17/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 6 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 6 × 20 = 120,
4/6 = 4 × 20/6 × 20 = 80/120 - Subtract the two like fractions:
63/120 - 80/120 = 63 - 80/120 = -17/120
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