Add 81/42 and 20/21
1st number: 1 39/42, 2nd number: 20/21
81/42 + 20/21 is 121/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42 - Add the two like fractions:
81/42 + 40/42 = 81 + 40/42 = 121/42 - So, 81/42 + 20/21 = 121/42
In mixed form: 237/42
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