Subtract 42/16 from 21/20
1st number: 1 1/20, 2nd number: 2 10/16
21/20 - 42/16 is -63/40.
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,
21/20 = 21 × 4/20 × 4 = 84/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
42/16 = 42 × 5/16 × 5 = 210/80 - Subtract the two like fractions:
84/80 - 210/80 = 84 - 210/80 = -126/80 - After reducing the fraction, the answer is -63/40
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