Add 72/18 and 21/8, Solve 4 0/18 + 2 5/8 as a fraction

Add 72/18 and 21/8

1^st number: 4 0/18, 2^nd number: 2 5/8

72/18 + 21/8 is 53/8.

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,
72/18 = 72 × 4/18 × 4 = 288/72
Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72
Add the two like fractions:
288/72 + 189/72 = 288 + 189/72 = 477/72
477/72 simplified gives 53/8
So, 72/18 + 21/8 = 53/8
In mixed form: 65/8

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