Add 8/12 and 72/21
1st number: 8/12, 2nd number: 3 9/21
8/12 + 72/21 is 86/21.
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,
8/12 = 8 × 7/12 × 7 = 56/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Add the two like fractions:
56/84 + 288/84 = 56 + 288/84 = 344/84 - 344/84 simplified gives 86/21
- So, 8/12 + 72/21 = 86/21
In mixed form: 42/21
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