Add 81/84 and 42/63
81/84 + 42/63 is 137/84.
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,
81/84 = 81 × 3/84 × 3 = 243/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Add the two like fractions:
243/252 + 168/252 = 243 + 168/252 = 411/252 - 411/252 simplified gives 137/84
- So, 81/84 + 42/63 = 137/84
In mixed form: 153/84
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Related: 81/84+84/63