Add 28/80 and 21/30
28/80 + 21/30 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 30 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
28/80 = 28 × 3/80 × 3 = 84/240 - Likewise, for the 2nd fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Add the two like fractions:
84/240 + 168/240 = 84 + 168/240 = 252/240 - 252/240 simplified gives 21/20
- So, 28/80 + 21/30 = 21/20
In mixed form: 11/20
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