Add 21/27 and 28/21, Solve 21/27 + 1 7/21 as a fraction

Add 21/27 and 28/21

1^st number: 21/27, 2^nd number: 1 7/21

21/27 + 28/21 is 19/9.

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

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
28/21 = 28 × 9/21 × 9 = 252/189
Add the two like fractions:
147/189 + 252/189 = 147 + 252/189 = 399/189
399/189 simplified gives 19/9
So, 21/27 + 28/21 = 19/9
In mixed form: 21/9

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