Add 81/21 and 30/28
1st number: 3 18/21, 2nd number: 1 2/28
81/21 + 30/28 is 69/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 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 28 × 3 = 84,
30/28 = 30 × 3/28 × 3 = 90/84 - Add the two like fractions:
324/84 + 90/84 = 324 + 90/84 = 414/84 - 414/84 simplified gives 69/14
- So, 81/21 + 30/28 = 69/14
In mixed form: 413/14
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