Subtract 20/42 from 81/4
1st number: 20 1/4, 2nd number: 20/42
81/4 - 20/42 is 1661/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Subtract the two like fractions:
1701/84 - 40/84 = 1701 - 40/84 = 1661/84 - In mixed form: 1965/84
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