Add 20/21 and 90/5
1st number: 20/21, 2nd number: 18 0/5
20/21 + 90/5 is 398/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
90/5 = 90 × 21/5 × 21 = 1890/105 - Add the two like fractions:
100/105 + 1890/105 = 100 + 1890/105 = 1990/105 - 1990/105 simplified gives 398/21
- So, 20/21 + 90/5 = 398/21
In mixed form: 1820/21
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