Add 81/21 and 70/84
1st number: 3 18/21, 2nd number: 70/84
81/21 + 70/84 is 197/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
70/84 = 70 × 1/84 × 1 = 70/84 - Add the two like fractions:
324/84 + 70/84 = 324 + 70/84 = 394/84 - 394/84 simplified gives 197/42
- So, 81/21 + 70/84 = 197/42
In mixed form: 429/42
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