Add 18/15 and 21/18
1st number: 1 3/15, 2nd number: 1 3/18
18/15 + 21/18 is 71/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
18/15 = 18 × 6/15 × 6 = 108/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
108/90 + 105/90 = 108 + 105/90 = 213/90 - 213/90 simplified gives 71/30
- So, 18/15 + 21/18 = 71/30
In mixed form: 211/30
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