Add 21/18 and 15/8, Solve 1 3/18 + 1 7/8 as a fraction

Add 21/18 and 15/8

1^st number: 1 3/18, 2^nd number: 1 7/8

21/18 + 15/8 is 73/24.

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,
21/18 = 21 × 4/18 × 4 = 84/72
Likewise, for the 2nd fraction, since 8 × 9 = 72,
15/8 = 15 × 9/8 × 9 = 135/72
Add the two like fractions:
84/72 + 135/72 = 84 + 135/72 = 219/72
219/72 simplified gives 73/24
So, 21/18 + 15/8 = 73/24
In mixed form: 31/24

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