Add 81/72 and 18/9, Solve 1 9/72 + 2 0/9 as a fraction

Add 81/72 and 18/9

1^st number: 1 9/72, 2^nd number: 2 0/9

81/72 + 18/9 is 25/8.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72
Likewise, for the 2nd fraction, since 9 × 8 = 72,
18/9 = 18 × 8/9 × 8 = 144/72
Add the two like fractions:
81/72 + 144/72 = 81 + 144/72 = 225/72
225/72 simplified gives 25/8
So, 81/72 + 18/9 = 25/8
In mixed form: 31/8

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