Subtract 20/21 from 90/5
1st number: 18 0/5, 2nd number: 20/21
90/5 - 20/21 is 358/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Subtract the two like fractions:
1890/105 - 100/105 = 1890 - 100/105 = 1790/105 - After reducing the fraction, the answer is 358/21
- In mixed form: 171/21
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