Add 21/2 and 28/21
1st number: 10 1/2, 2nd number: 1 7/21
21/2 + 28/21 is 71/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
21/2 = 21 × 21/2 × 21 = 441/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
28/21 = 28 × 2/21 × 2 = 56/42 - Add the two like fractions:
441/42 + 56/42 = 441 + 56/42 = 497/42 - 497/42 simplified gives 71/6
- So, 21/2 + 28/21 = 71/6
In mixed form: 115/6
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