Add 21/9 and 81/42
1st number: 2 3/9, 2nd number: 1 39/42
21/9 + 81/42 is 179/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 9 × 14 = 126,
21/9 = 21 × 14/9 × 14 = 294/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
81/42 = 81 × 3/42 × 3 = 243/126 - Add the two like fractions:
294/126 + 243/126 = 294 + 243/126 = 537/126 - 537/126 simplified gives 179/42
- So, 21/9 + 81/42 = 179/42
In mixed form: 411/42
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