Add 21/81 and 6/16, Solve 21/81 + 6/16 as a fraction

Add 21/81 and 6/16

21/81 + 6/16 is 137/216.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 16 is 1296

Next, find the equivalent fraction of both fractional numbers with denominator 1296
For the 1st fraction, since 81 × 16 = 1296,
21/81 = 21 × 16/81 × 16 = 336/1296
Likewise, for the 2nd fraction, since 16 × 81 = 1296,
6/16 = 6 × 81/16 × 81 = 486/1296
Add the two like fractions:
336/1296 + 486/1296 = 336 + 486/1296 = 822/1296
822/1296 simplified gives 137/216
So, 21/81 + 6/16 = 137/216

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