Add 18/5 and 21/18
1st number: 3 3/5, 2nd number: 1 3/18
18/5 + 21/18 is 143/30.
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,
18/5 = 18 × 18/5 × 18 = 324/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
324/90 + 105/90 = 324 + 105/90 = 429/90 - 429/90 simplified gives 143/30
- So, 18/5 + 21/18 = 143/30
In mixed form: 423/30
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