Subtract 21/16 from 42/40
1st number: 1 2/40, 2nd number: 1 5/16
42/40 - 21/16 is -21/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
42/40 = 42 × 2/40 × 2 = 84/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
21/16 = 21 × 5/16 × 5 = 105/80 - Subtract the two like fractions:
84/80 - 105/80 = 84 - 105/80 = -21/80
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