Subtract 1/21 from 90/20
1st number: 4 10/20, 2nd number: 1/21
90/20 - 1/21 is 187/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
1/21 = 1 × 20/21 × 20 = 20/420 - Subtract the two like fractions:
1890/420 - 20/420 = 1890 - 20/420 = 1870/420 - After reducing the fraction, the answer is 187/42
- In mixed form: 419/42
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