Subtract 81/4 from 42/10
1st number: 4 2/10, 2nd number: 20 1/4
42/10 - 81/4 is -321/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 4 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 10 × 2 = 20,
42/10 = 42 × 2/10 × 2 = 84/20 - Likewise, for the 2nd fraction, since 4 × 5 = 20,
81/4 = 81 × 5/4 × 5 = 405/20 - Subtract the two like fractions:
84/20 - 405/20 = 84 - 405/20 = -321/20
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