Add 21/18 and 7/21
1st number: 1 3/18, 2nd number: 7/21
21/18 + 7/21 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
7/21 = 7 × 6/21 × 6 = 42/126 - Add the two like fractions:
147/126 + 42/126 = 147 + 42/126 = 189/126 - 189/126 simplified gives 3/2
- So, 21/18 + 7/21 = 3/2
In mixed form: 11/2
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