Add 81/21 and 90/8
1st number: 3 18/21, 2nd number: 11 2/8
81/21 + 90/8 is 423/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
90/8 = 90 × 21/8 × 21 = 1890/168 - Add the two like fractions:
648/168 + 1890/168 = 648 + 1890/168 = 2538/168 - 2538/168 simplified gives 423/28
- So, 81/21 + 90/8 = 423/28
In mixed form: 153/28
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