Add 18/27 and 25/21, Solve 18/27 + 1 4/21 as a fraction

Add 18/27 and 25/21

1^st number: 18/27, 2^nd number: 1 4/21

18/27 + 25/21 is 13/7.

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,
18/27 = 18 × 7/27 × 7 = 126/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
25/21 = 25 × 9/21 × 9 = 225/189
Add the two like fractions:
126/189 + 225/189 = 126 + 225/189 = 351/189
351/189 simplified gives 13/7
So, 18/27 + 25/21 = 13/7
In mixed form: 16/7

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