Subtract 21/16 from 15/20
1st number: 15/20, 2nd number: 1 5/16
15/20 - 21/16 is -9/16.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
15/20 = 15 × 4/20 × 4 = 60/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
21/16 = 21 × 5/16 × 5 = 105/80 - Subtract the two like fractions:
60/80 - 105/80 = 60 - 105/80 = -45/80 - After reducing the fraction, the answer is -9/16
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