Add 30/21 and 63/27, Solve 1 9/21 + 2 9/27 as a fraction

Add 30/21 and 63/27

1^st number: 1 9/21, 2^nd number: 2 9/27

30/21 + 63/27 is 79/21.

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,
30/21 = 30 × 9/21 × 9 = 270/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
63/27 = 63 × 7/27 × 7 = 441/189
Add the two like fractions:
270/189 + 441/189 = 270 + 441/189 = 711/189
711/189 simplified gives 79/21
So, 30/21 + 63/27 = 79/21
In mixed form: 316/21

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