Add 21/8 and 15/27, Solve 2 5/8 + 15/27 as a fraction

Add 21/8 and 15/27

1^st number: 2 5/8, 2^nd number: 15/27

21/8 + 15/27 is 229/72.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 27 is 216

Next, find the equivalent fraction of both fractional numbers with denominator 216
For the 1st fraction, since 8 × 27 = 216,
21/8 = 21 × 27/8 × 27 = 567/216
Likewise, for the 2nd fraction, since 27 × 8 = 216,
15/27 = 15 × 8/27 × 8 = 120/216
Add the two like fractions:
567/216 + 120/216 = 567 + 120/216 = 687/216
687/216 simplified gives 229/72
So, 21/8 + 15/27 = 229/72
In mixed form: 313/72

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