Add 7/21 and 21/27, Solve 7/21 + 21/27 as a fraction

Add 7/21 and 21/27

7/21 + 21/27 is 10/9.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
7/21 = 7 × 9/21 × 9 = 63/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189
Add the two like fractions:
63/189 + 147/189 = 63 + 147/189 = 210/189
210/189 simplified gives 10/9
So, 7/21 + 21/27 = 10/9
In mixed form: 11/9

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