Subtract 21/3 from 18/40
1st number: 18/40, 2nd number: 7 0/3
18/40 - 21/3 is -131/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 3 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
18/40 = 18 × 3/40 × 3 = 54/120 - Likewise, for the 2nd fraction, since 3 × 40 = 120,
21/3 = 21 × 40/3 × 40 = 840/120 - Subtract the two like fractions:
54/120 - 840/120 = 54 - 840/120 = -786/120 - After reducing the fraction, the answer is -131/20
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