Add 3/21 and 42/27, Solve 3/21 + 1 15/27 as a fraction

Add 3/21 and 42/27

1^st number: 3/21, 2^nd number: 1 15/27

3/21 + 42/27 is 107/63.

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,
3/21 = 3 × 9/21 × 9 = 27/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
42/27 = 42 × 7/27 × 7 = 294/189
Add the two like fractions:
27/189 + 294/189 = 27 + 294/189 = 321/189
321/189 simplified gives 107/63
So, 3/21 + 42/27 = 107/63
In mixed form: 144/63

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