Add 45/12 and 80/21
1st number: 3 9/12, 2nd number: 3 17/21
45/12 + 80/21 is 635/84.
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,
45/12 = 45 × 7/12 × 7 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Add the two like fractions:
315/84 + 320/84 = 315 + 320/84 = 635/84 - So, 45/12 + 80/21 = 635/84
In mixed form: 747/84
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