Add 72/21 and 12/9
1st number: 3 9/21, 2nd number: 1 3/9
72/21 + 12/9 is 100/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Add the two like fractions:
216/63 + 84/63 = 216 + 84/63 = 300/63 - 300/63 simplified gives 100/21
- So, 72/21 + 12/9 = 100/21
In mixed form: 416/21
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