Add 21/4 and 21/18
1st number: 5 1/4, 2nd number: 1 3/18
21/4 + 21/18 is 77/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Add the two like fractions:
189/36 + 42/36 = 189 + 42/36 = 231/36 - 231/36 simplified gives 77/12
- So, 21/4 + 21/18 = 77/12
In mixed form: 65/12
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