Add 28/8 and 81/21
1st number: 3 4/8, 2nd number: 3 18/21
28/8 + 81/21 is 103/14.
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,
28/8 = 28 × 21/8 × 21 = 588/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Add the two like fractions:
588/168 + 648/168 = 588 + 648/168 = 1236/168 - 1236/168 simplified gives 103/14
- So, 28/8 + 81/21 = 103/14
In mixed form: 75/14
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