Add 30/21 and 81/8
1st number: 1 9/21, 2nd number: 10 1/8
30/21 + 81/8 is 647/56.
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,
30/21 = 30 × 8/21 × 8 = 240/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
81/8 = 81 × 21/8 × 21 = 1701/168 - Add the two like fractions:
240/168 + 1701/168 = 240 + 1701/168 = 1941/168 - 1941/168 simplified gives 647/56
- So, 30/21 + 81/8 = 647/56
In mixed form: 1131/56
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