Add 42/27 and 9/21, Solve 1 15/27 + 9/21 as a fraction

Add 42/27 and 9/21

1^st number: 1 15/27, 2^nd number: 9/21

42/27 + 9/21 is 125/63.

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,
9/21 = 9 × 9/21 × 9 = 81/189
Add the two like fractions:
294/189 + 81/189 = 294 + 81/189 = 375/189
375/189 simplified gives 125/63
So, 42/27 + 9/21 = 125/63
In mixed form: 162/63

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