Add 45/54 and 40/21, Solve 45/54 + 1 19/21 as a fraction

Add 45/54 and 40/21

1^st number: 45/54, 2^nd number: 1 19/21

45/54 + 40/21 is 115/42.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
45/54 = 45 × 7/54 × 7 = 315/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
40/21 = 40 × 18/21 × 18 = 720/378
Add the two like fractions:
315/378 + 720/378 = 315 + 720/378 = 1035/378
1035/378 simplified gives 115/42
So, 45/54 + 40/21 = 115/42
In mixed form: 231/42

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