Add 12/21 and 28/20
1st number: 12/21, 2nd number: 1 8/20
12/21 + 28/20 is 69/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
12/21 = 12 × 20/21 × 20 = 240/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
28/20 = 28 × 21/20 × 21 = 588/420 - Add the two like fractions:
240/420 + 588/420 = 240 + 588/420 = 828/420 - 828/420 simplified gives 69/35
- So, 12/21 + 28/20 = 69/35
In mixed form: 134/35
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