Add 21/18 and 21/30
1st number: 1 3/18, 2nd number: 21/30
21/18 + 21/30 is 28/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Add the two like fractions:
105/90 + 63/90 = 105 + 63/90 = 168/90 - 168/90 simplified gives 28/15
- So, 21/18 + 21/30 = 28/15
In mixed form: 113/15
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