Add 81/18 and 6/8, Solve 4 9/18 + 6/8 as a fraction

Add 81/18 and 6/8

1^st number: 4 9/18, 2^nd number: 6/8

81/18 + 6/8 is 21/4.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 18 × 4 = 72,
81/18 = 81 × 4/18 × 4 = 324/72
Likewise, for the 2nd fraction, since 8 × 9 = 72,
6/8 = 6 × 9/8 × 9 = 54/72
Add the two like fractions:
324/72 + 54/72 = 324 + 54/72 = 378/72
378/72 simplified gives 21/4
So, 81/18 + 6/8 = 21/4
In mixed form: 51/4

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