Subtract 20/54 from 21/7
1st number: 3 0/7, 2nd number: 20/54
21/7 - 20/54 is 71/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 7 × 54 = 378,
21/7 = 21 × 54/7 × 54 = 1134/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378 - Subtract the two like fractions:
1134/378 - 140/378 = 1134 - 140/378 = 994/378 - After reducing the fraction, the answer is 71/27
- In mixed form: 217/27
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