Add 21/14 and 28/21
1st number: 1 7/14, 2nd number: 1 7/21
21/14 + 28/21 is 17/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 14 × 3 = 42,
21/14 = 21 × 3/14 × 3 = 63/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
28/21 = 28 × 2/21 × 2 = 56/42 - Add the two like fractions:
63/42 + 56/42 = 63 + 56/42 = 119/42 - 119/42 simplified gives 17/6
- So, 21/14 + 28/21 = 17/6
In mixed form: 25/6
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