Add 18/8 and 81/21
1st number: 2 2/8, 2nd number: 3 18/21
18/8 + 81/21 is 171/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
18/8 = 18 × 21/8 × 21 = 378/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Add the two like fractions:
378/168 + 648/168 = 378 + 648/168 = 1026/168 - 1026/168 simplified gives 171/28
- So, 18/8 + 81/21 = 171/28
In mixed form: 63/28
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