Add 80/21 and 18/5
1st number: 3 17/21, 2nd number: 3 3/5
80/21 + 18/5 is 778/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
18/5 = 18 × 21/5 × 21 = 378/105 - Add the two like fractions:
400/105 + 378/105 = 400 + 378/105 = 778/105 - So, 80/21 + 18/5 = 778/105
In mixed form: 743/105
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