Add 72/21 and 81/54
1st number: 3 9/21, 2nd number: 1 27/54
72/21 + 81/54 is 69/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
72/21 = 72 × 18/21 × 18 = 1296/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
81/54 = 81 × 7/54 × 7 = 567/378 - Add the two like fractions:
1296/378 + 567/378 = 1296 + 567/378 = 1863/378 - 1863/378 simplified gives 69/14
- So, 72/21 + 81/54 = 69/14
In mixed form: 413/14
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