Add 70/8 and 81/21
1st number: 8 6/8, 2nd number: 3 18/21
70/8 + 81/21 is 353/28.
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,
70/8 = 70 × 21/8 × 21 = 1470/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Add the two like fractions:
1470/168 + 648/168 = 1470 + 648/168 = 2118/168 - 2118/168 simplified gives 353/28
- So, 70/8 + 81/21 = 353/28
In mixed form: 1217/28
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