Add 18/21 and 84/12
1st number: 18/21, 2nd number: 7 0/12
18/21 + 84/12 is 55/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
84/12 = 84 × 7/12 × 7 = 588/84 - Add the two like fractions:
72/84 + 588/84 = 72 + 588/84 = 660/84 - 660/84 simplified gives 55/7
- So, 18/21 + 84/12 = 55/7
In mixed form: 76/7
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