Add 21/80 and 18/5
1st number: 21/80, 2nd number: 3 3/5
21/80 + 18/5 is 309/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 5 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 5 × 16 = 80,
18/5 = 18 × 16/5 × 16 = 288/80 - Add the two like fractions:
21/80 + 288/80 = 21 + 288/80 = 309/80 - So, 21/80 + 18/5 = 309/80
In mixed form: 369/80
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