Add 72/12 and 45/21
1st number: 6 0/12, 2nd number: 2 3/21
72/12 + 45/21 is 57/7.
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,
72/12 = 72 × 7/12 × 7 = 504/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
45/21 = 45 × 4/21 × 4 = 180/84 - Add the two like fractions:
504/84 + 180/84 = 504 + 180/84 = 684/84 - 684/84 simplified gives 57/7
- So, 72/12 + 45/21 = 57/7
In mixed form: 81/7
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