Add 9/21 and 12/7
1st number: 9/21, 2nd number: 1 5/7
9/21 + 12/7 is 15/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
9/21 = 9 × 1/21 × 1 = 9/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
12/7 = 12 × 3/7 × 3 = 36/21 - Add the two like fractions:
9/21 + 36/21 = 9 + 36/21 = 45/21 - 45/21 simplified gives 15/7
- So, 9/21 + 12/7 = 15/7
In mixed form: 21/7
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