Add 21/84 and 84/63
1st number: 21/84, 2nd number: 1 21/63
21/84 + 84/63 is 19/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
84/63 = 84 × 4/63 × 4 = 336/252 - Add the two like fractions:
63/252 + 336/252 = 63 + 336/252 = 399/252 - 399/252 simplified gives 19/12
- So, 21/84 + 84/63 = 19/12
In mixed form: 17/12
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