Add 20/5 and 28/21
1st number: 4 0/5, 2nd number: 1 7/21
20/5 + 28/21 is 16/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
20/5 = 20 × 21/5 × 21 = 420/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Add the two like fractions:
420/105 + 140/105 = 420 + 140/105 = 560/105 - 560/105 simplified gives 16/3
- So, 20/5 + 28/21 = 16/3
In mixed form: 51/3
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