Subtract 81/20 from 42/2
1st number: 21 0/2, 2nd number: 4 1/20
42/2 - 81/20 is 339/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 2 × 10 = 20,
42/2 = 42 × 10/2 × 10 = 420/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
81/20 = 81 × 1/20 × 1 = 81/20 - Subtract the two like fractions:
420/20 - 81/20 = 420 - 81/20 = 339/20 - In mixed form: 1619/20
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