Add 30/21 and 40/54, Solve 1 9/21 + 40/54 as a fraction

Add 30/21 and 40/54

1^st number: 1 9/21, 2^nd number: 40/54

30/21 + 40/54 is 410/189.

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

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
30/21 = 30 × 18/21 × 18 = 540/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
40/54 = 40 × 7/54 × 7 = 280/378
Add the two like fractions:
540/378 + 280/378 = 540 + 280/378 = 820/378
820/378 simplified gives 410/189
So, 30/21 + 40/54 = 410/189
In mixed form: 232/189

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