Add 28/21 and 21/80
1st number: 1 7/21, 2nd number: 21/80
28/21 + 21/80 is 383/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680 - Add the two like fractions:
2240/1680 + 441/1680 = 2240 + 441/1680 = 2681/1680 - 2681/1680 simplified gives 383/240
- So, 28/21 + 21/80 = 383/240
In mixed form: 1143/240
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