Subtract 15/8 from 21/40
1st number: 21/40, 2nd number: 1 7/8
21/40 - 15/8 is -27/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
21/40 = 21 × 1/40 × 1 = 21/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
15/8 = 15 × 5/8 × 5 = 75/40 - Subtract the two like fractions:
21/40 - 75/40 = 21 - 75/40 = -54/40 - After reducing the fraction, the answer is -27/20
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