Add 21/18 and 81/4
1st number: 1 3/18, 2nd number: 20 1/4
21/18 + 81/4 is 257/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 4 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Likewise, for the 2nd fraction, since 4 × 9 = 36,
81/4 = 81 × 9/4 × 9 = 729/36 - Add the two like fractions:
42/36 + 729/36 = 42 + 729/36 = 771/36 - 771/36 simplified gives 257/12
- So, 21/18 + 81/4 = 257/12
In mixed form: 215/12
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