Add 12/7 and 21/9
1st number: 1 5/7, 2nd number: 2 3/9
12/7 + 21/9 is 85/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
12/7 = 12 × 9/7 × 9 = 108/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
21/9 = 21 × 7/9 × 7 = 147/63 - Add the two like fractions:
108/63 + 147/63 = 108 + 147/63 = 255/63 - 255/63 simplified gives 85/21
- So, 12/7 + 21/9 = 85/21
In mixed form: 41/21
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