Add 90/2 and 81/21
1st number: 45 0/2, 2nd number: 3 18/21
90/2 + 81/21 is 342/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
90/2 = 90 × 21/2 × 21 = 1890/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Add the two like fractions:
1890/42 + 162/42 = 1890 + 162/42 = 2052/42 - 2052/42 simplified gives 342/7
- So, 90/2 + 81/21 = 342/7
In mixed form: 486/7
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