Add 54/21 and 81/84
1st number: 2 12/21, 2nd number: 81/84
54/21 + 81/84 is 99/28.
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,
54/21 = 54 × 4/21 × 4 = 216/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
81/84 = 81 × 1/84 × 1 = 81/84 - Add the two like fractions:
216/84 + 81/84 = 216 + 81/84 = 297/84 - 297/84 simplified gives 99/28
- So, 54/21 + 81/84 = 99/28
In mixed form: 315/28
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