Subtract 20/42 from 54/21
1st number: 2 12/21, 2nd number: 20/42
54/21 - 20/42 is 44/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
54/21 = 54 × 2/21 × 2 = 108/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42 - Subtract the two like fractions:
108/42 - 20/42 = 108 - 20/42 = 88/42 - After reducing the fraction, the answer is 44/21
- In mixed form: 22/21
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