Add 28/80 and 21/20
1st number: 28/80, 2nd number: 1 1/20
28/80 + 21/20 is 7/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
28/80 = 28 × 1/80 × 1 = 28/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
21/20 = 21 × 4/20 × 4 = 84/80 - Add the two like fractions:
28/80 + 84/80 = 28 + 84/80 = 112/80 - 112/80 simplified gives 7/5
- So, 28/80 + 21/20 = 7/5
In mixed form: 12/5
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