Add 21/5 and 15/18
1st number: 4 1/5, 2nd number: 15/18
21/5 + 15/18 is 151/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
15/18 = 15 × 5/18 × 5 = 75/90 - Add the two like fractions:
378/90 + 75/90 = 378 + 75/90 = 453/90 - 453/90 simplified gives 151/30
- So, 21/5 + 15/18 = 151/30
In mixed form: 51/30
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