Add 72/12 and 81/21
1st number: 6 0/12, 2nd number: 3 18/21
72/12 + 81/21 is 69/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
72/12 = 72 × 7/12 × 7 = 504/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Add the two like fractions:
504/84 + 324/84 = 504 + 324/84 = 828/84 - 828/84 simplified gives 69/7
- So, 72/12 + 81/21 = 69/7
In mixed form: 96/7
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