Add 21/30 and 18/15
1st number: 21/30, 2nd number: 1 3/15
21/30 + 18/15 is 19/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 15 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Likewise, for the 2nd fraction, since 15 × 2 = 30,
18/15 = 18 × 2/15 × 2 = 36/30 - Add the two like fractions:
21/30 + 36/30 = 21 + 36/30 = 57/30 - 57/30 simplified gives 19/10
- So, 21/30 + 18/15 = 19/10
In mixed form: 19/10
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