Add 21/7 and 45/18
1st number: 3 0/7, 2nd number: 2 9/18
21/7 + 45/18 is 11/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
21/7 = 21 × 18/7 × 18 = 378/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
45/18 = 45 × 7/18 × 7 = 315/126 - Add the two like fractions:
378/126 + 315/126 = 378 + 315/126 = 693/126 - 693/126 simplified gives 11/2
- So, 21/7 + 45/18 = 11/2
In mixed form: 51/2
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