Add 80/12 and 30/21
1st number: 6 8/12, 2nd number: 1 9/21
80/12 + 30/21 is 170/21.
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,
80/12 = 80 × 7/12 × 7 = 560/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Add the two like fractions:
560/84 + 120/84 = 560 + 120/84 = 680/84 - 680/84 simplified gives 170/21
- So, 80/12 + 30/21 = 170/21
In mixed form: 82/21
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