Subtract 15/3 from 21/40
1st number: 21/40, 2nd number: 5 0/3
21/40 - 15/3 is -179/40.
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,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 3 × 40 = 120,
15/3 = 15 × 40/3 × 40 = 600/120 - Subtract the two like fractions:
63/120 - 600/120 = 63 - 600/120 = -537/120 - After reducing the fraction, the answer is -179/40
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