Add 54/81 and 21/8, Solve 54/81 + 2 5/8 as a fraction

Add 54/81 and 21/8

1^st number: 54/81, 2^nd number: 2 5/8

54/81 + 21/8 is 79/24.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 8 is 648

Next, find the equivalent fraction of both fractional numbers with denominator 648
For the 1st fraction, since 81 × 8 = 648,
54/81 = 54 × 8/81 × 8 = 432/648
Likewise, for the 2nd fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648
Add the two like fractions:
432/648 + 1701/648 = 432 + 1701/648 = 2133/648
2133/648 simplified gives 79/24
So, 54/81 + 21/8 = 79/24
In mixed form: 37/24

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