Add 42/27 and 75/21, Solve 1 15/27 + 3 12/21 as a fraction

Add 42/27 and 75/21

1^st number: 1 15/27, 2^nd number: 3 12/21

42/27 + 75/21 is 323/63.

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,
42/27 = 42 × 7/27 × 7 = 294/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
75/21 = 75 × 9/21 × 9 = 675/189
Add the two like fractions:
294/189 + 675/189 = 294 + 675/189 = 969/189
969/189 simplified gives 323/63
So, 42/27 + 75/21 = 323/63
In mixed form: 58/63

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