Add 21/84 and 45/63
21/84 + 45/63 is 27/28.
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,
45/63 = 45 × 4/63 × 4 = 180/252 - Add the two like fractions:
63/252 + 180/252 = 63 + 180/252 = 243/252 - 243/252 simplified gives 27/28
- So, 21/84 + 45/63 = 27/28
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