Add 81/21 and 20/36
1st number: 3 18/21, 2nd number: 20/36
81/21 + 20/36 is 278/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
81/21 = 81 × 12/21 × 12 = 972/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Add the two like fractions:
972/252 + 140/252 = 972 + 140/252 = 1112/252 - 1112/252 simplified gives 278/63
- So, 81/21 + 20/36 = 278/63
In mixed form: 426/63
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