Add 81/42 and 12/21
1st number: 1 39/42, 2nd number: 12/21
81/42 + 12/21 is 5/2.
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,
12/21 = 12 × 2/21 × 2 = 24/42 - Add the two like fractions:
81/42 + 24/42 = 81 + 24/42 = 105/42 - 105/42 simplified gives 5/2
- So, 81/42 + 12/21 = 5/2
In mixed form: 21/2
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