Add 18/5 and 42/21
1st number: 3 3/5, 2nd number: 2 0/21
18/5 + 42/21 is 28/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
18/5 = 18 × 21/5 × 21 = 378/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Add the two like fractions:
378/105 + 210/105 = 378 + 210/105 = 588/105 - 588/105 simplified gives 28/5
- So, 18/5 + 42/21 = 28/5
In mixed form: 53/5
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