Add 18/5 and 40/21
1st number: 3 3/5, 2nd number: 1 19/21
18/5 + 40/21 is 578/105.
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,
40/21 = 40 × 5/21 × 5 = 200/105 - Add the two like fractions:
378/105 + 200/105 = 378 + 200/105 = 578/105 - So, 18/5 + 40/21 = 578/105
In mixed form: 553/105
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