Add 45/42 and 21/27, Solve 1 3/42 + 21/27 as a fraction

Add 45/42 and 21/27

1^st number: 1 3/42, 2^nd number: 21/27

45/42 + 21/27 is 233/126.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
45/42 = 45 × 9/42 × 9 = 405/378
Likewise, for the 2nd fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378
Add the two like fractions:
405/378 + 294/378 = 405 + 294/378 = 699/378
699/378 simplified gives 233/126
So, 45/42 + 21/27 = 233/126
In mixed form: 1107/126

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