Add 72/21 and 84/36
1st number: 3 9/21, 2nd number: 2 12/36
72/21 + 84/36 is 121/21.
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,
72/21 = 72 × 12/21 × 12 = 864/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
84/36 = 84 × 7/36 × 7 = 588/252 - Add the two like fractions:
864/252 + 588/252 = 864 + 588/252 = 1452/252 - 1452/252 simplified gives 121/21
- So, 72/21 + 84/36 = 121/21
In mixed form: 516/21
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