Subtract 21/8 from 42/20
1st number: 2 2/20, 2nd number: 2 5/8
42/20 - 21/8 is -21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
42/20 = 42 × 2/20 × 2 = 84/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Subtract the two like fractions:
84/40 - 105/40 = 84 - 105/40 = -21/40
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