Add 12/4 and 80/21
1st number: 3 0/4, 2nd number: 3 17/21
12/4 + 80/21 is 143/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
12/4 = 12 × 21/4 × 21 = 252/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Add the two like fractions:
252/84 + 320/84 = 252 + 320/84 = 572/84 - 572/84 simplified gives 143/21
- So, 12/4 + 80/21 = 143/21
In mixed form: 617/21
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