Subtract 42/8 from 21/5
1st number: 4 1/5, 2nd number: 5 2/8
21/5 - 42/8 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
42/8 = 42 × 5/8 × 5 = 210/40 - Subtract the two like fractions:
168/40 - 210/40 = 168 - 210/40 = -42/40 - After reducing the fraction, the answer is -21/20
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