Add 9/21 and 21/8
1st number: 9/21, 2nd number: 2 5/8
9/21 + 21/8 is 171/56.
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,
9/21 = 9 × 8/21 × 8 = 72/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168 - Add the two like fractions:
72/168 + 441/168 = 72 + 441/168 = 513/168 - 513/168 simplified gives 171/56
- So, 9/21 + 21/8 = 171/56
In mixed form: 33/56
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