Subtract 81/8 from 42/5
1st number: 8 2/5, 2nd number: 10 1/8
42/5 - 81/8 is -69/40.
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,
42/5 = 42 × 8/5 × 8 = 336/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
81/8 = 81 × 5/8 × 5 = 405/40 - Subtract the two like fractions:
336/40 - 405/40 = 336 - 405/40 = -69/40
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