Subtract 63/42 from 81/20
1st number: 4 1/20, 2nd number: 1 21/42
81/20 - 63/42 is 51/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
81/20 = 81 × 21/20 × 21 = 1701/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
63/42 = 63 × 10/42 × 10 = 630/420 - Subtract the two like fractions:
1701/420 - 630/420 = 1701 - 630/420 = 1071/420 - After reducing the fraction, the answer is 51/20
- In mixed form: 211/20
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