Add 12/21 and 81/20
1st number: 12/21, 2nd number: 4 1/20
12/21 + 81/20 is 647/140.
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,
81/20 = 81 × 21/20 × 21 = 1701/420 - Add the two like fractions:
240/420 + 1701/420 = 240 + 1701/420 = 1941/420 - 1941/420 simplified gives 647/140
- So, 12/21 + 81/20 = 647/140
In mixed form: 487/140
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