Add 21/18 and 42/8
1st number: 1 3/18, 2nd number: 5 2/8
21/18 + 42/8 is 77/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
42/8 = 42 × 9/8 × 9 = 378/72 - Add the two like fractions:
84/72 + 378/72 = 84 + 378/72 = 462/72 - 462/72 simplified gives 77/12
- So, 21/18 + 42/8 = 77/12
In mixed form: 65/12
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