Add 81/21 and 70/28
1st number: 3 18/21, 2nd number: 2 14/28
81/21 + 70/28 is 89/14.
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,
70/28 = 70 × 3/28 × 3 = 210/84 - Add the two like fractions:
324/84 + 210/84 = 324 + 210/84 = 534/84 - 534/84 simplified gives 89/14
- So, 81/21 + 70/28 = 89/14
In mixed form: 65/14
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