Add 40/21 and 54/81
1st number: 1 19/21, 2nd number: 54/81
40/21 + 54/81 is 18/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
40/21 = 40 × 27/21 × 27 = 1080/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
54/81 = 54 × 7/81 × 7 = 378/567 - Add the two like fractions:
1080/567 + 378/567 = 1080 + 378/567 = 1458/567 - 1458/567 simplified gives 18/7
- So, 40/21 + 54/81 = 18/7
In mixed form: 24/7
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