Add 15/18 and 21/15
1st number: 15/18, 2nd number: 1 6/15
15/18 + 21/15 is 67/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 15 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
15/18 = 15 × 5/18 × 5 = 75/90 - Likewise, for the 2nd fraction, since 15 × 6 = 90,
21/15 = 21 × 6/15 × 6 = 126/90 - Add the two like fractions:
75/90 + 126/90 = 75 + 126/90 = 201/90 - 201/90 simplified gives 67/30
- So, 15/18 + 21/15 = 67/30
In mixed form: 27/30
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