Add 21/9 and 42/8
1st number: 2 3/9, 2nd number: 5 2/8
21/9 + 42/8 is 91/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
42/8 = 42 × 9/8 × 9 = 378/72 - Add the two like fractions:
168/72 + 378/72 = 168 + 378/72 = 546/72 - 546/72 simplified gives 91/12
- So, 21/9 + 42/8 = 91/12
In mixed form: 77/12
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