Add 15/21 and 30/15
1st number: 15/21, 2nd number: 2 0/15
15/21 + 30/15 is 19/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 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 15 × 7 = 105,
30/15 = 30 × 7/15 × 7 = 210/105 - Add the two like fractions:
75/105 + 210/105 = 75 + 210/105 = 285/105 - 285/105 simplified gives 19/7
- So, 15/21 + 30/15 = 19/7
In mixed form: 25/7
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