Add 21/12 and 28/80
1st number: 1 9/12, 2nd number: 28/80
21/12 + 28/80 is 21/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
21/12 = 21 × 20/12 × 20 = 420/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
28/80 = 28 × 3/80 × 3 = 84/240 - Add the two like fractions:
420/240 + 84/240 = 420 + 84/240 = 504/240 - 504/240 simplified gives 21/10
- So, 21/12 + 28/80 = 21/10
In mixed form: 21/10
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