Add 81/84 and 72/18
1st number: 81/84, 2nd number: 4 0/18
81/84 + 72/18 is 139/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 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 18 × 14 = 252,
72/18 = 72 × 14/18 × 14 = 1008/252 - Add the two like fractions:
243/252 + 1008/252 = 243 + 1008/252 = 1251/252 - 1251/252 simplified gives 139/28
- So, 81/84 + 72/18 = 139/28
In mixed form: 427/28
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