Add 28/21 and 21/18
1st number: 1 7/21, 2nd number: 1 3/18
28/21 + 21/18 is 5/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
28/21 = 28 × 6/21 × 6 = 168/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
168/126 + 147/126 = 168 + 147/126 = 315/126 - 315/126 simplified gives 5/2
- So, 28/21 + 21/18 = 5/2
In mixed form: 21/2
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