Add 15/21 and 12/5
1st number: 15/21, 2nd number: 2 2/5
15/21 + 12/5 is 109/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
12/5 = 12 × 21/5 × 21 = 252/105 - Add the two like fractions:
75/105 + 252/105 = 75 + 252/105 = 327/105 - 327/105 simplified gives 109/35
- So, 15/21 + 12/5 = 109/35
In mixed form: 34/35
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