Add 28/4 and 81/21
1st number: 7 0/4, 2nd number: 3 18/21
28/4 + 81/21 is 76/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
28/4 = 28 × 21/4 × 21 = 588/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Add the two like fractions:
588/84 + 324/84 = 588 + 324/84 = 912/84 - 912/84 simplified gives 76/7
- So, 28/4 + 81/21 = 76/7
In mixed form: 106/7
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