Add 21/4 and 84/63
1st number: 5 1/4, 2nd number: 1 21/63
21/4 + 84/63 is 79/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 4 × 63 = 252,
21/4 = 21 × 63/4 × 63 = 1323/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
84/63 = 84 × 4/63 × 4 = 336/252 - Add the two like fractions:
1323/252 + 336/252 = 1323 + 336/252 = 1659/252 - 1659/252 simplified gives 79/12
- So, 21/4 + 84/63 = 79/12
In mixed form: 67/12
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