Add 12/20 and 81/42
1st number: 12/20, 2nd number: 1 39/42
12/20 + 81/42 is 177/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
81/42 = 81 × 10/42 × 10 = 810/420 - Add the two like fractions:
252/420 + 810/420 = 252 + 810/420 = 1062/420 - 1062/420 simplified gives 177/70
- So, 12/20 + 81/42 = 177/70
In mixed form: 237/70
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