Add 15/30 and 21/18
1st number: 15/30, 2nd number: 1 3/18
15/30 + 21/18 is 5/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
15/30 = 15 × 3/30 × 3 = 45/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
45/90 + 105/90 = 45 + 105/90 = 150/90 - 150/90 simplified gives 5/3
- So, 15/30 + 21/18 = 5/3
In mixed form: 12/3
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