Add 21/8 and 25/9
1st number: 2 5/8, 2nd number: 2 7/9
21/8 + 25/9 is 389/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
25/9 = 25 × 8/9 × 8 = 200/72 - Add the two like fractions:
189/72 + 200/72 = 189 + 200/72 = 389/72 - So, 21/8 + 25/9 = 389/72
In mixed form: 529/72
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