Subtract 42/20 from 21/16
1st number: 1 5/16, 2nd number: 2 2/20
21/16 - 42/20 is -63/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 16 × 5 = 80,
21/16 = 21 × 5/16 × 5 = 105/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
42/20 = 42 × 4/20 × 4 = 168/80 - Subtract the two like fractions:
105/80 - 168/80 = 105 - 168/80 = -63/80
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