Add 21/18 and 15/45
1st number: 1 3/18, 2nd number: 15/45
21/18 + 15/45 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 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 45 × 2 = 90,
15/45 = 15 × 2/45 × 2 = 30/90 - Add the two like fractions:
105/90 + 30/90 = 105 + 30/90 = 135/90 - 135/90 simplified gives 3/2
- So, 21/18 + 15/45 = 3/2
In mixed form: 11/2
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