Add 30/8 and 18/21
1st number: 3 6/8, 2nd number: 18/21
30/8 + 18/21 is 129/28.
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,
30/8 = 30 × 21/8 × 21 = 630/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168 - Add the two like fractions:
630/168 + 144/168 = 630 + 144/168 = 774/168 - 774/168 simplified gives 129/28
- So, 30/8 + 18/21 = 129/28
In mixed form: 417/28
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