Add 36/54 and 75/21, Solve 36/54 + 3 12/21 as a fraction

Add 36/54 and 75/21

1^st number: 36/54, 2^nd number: 3 12/21

36/54 + 75/21 is 89/21.

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,
36/54 = 36 × 7/54 × 7 = 252/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
75/21 = 75 × 18/21 × 18 = 1350/378
Add the two like fractions:
252/378 + 1350/378 = 252 + 1350/378 = 1602/378
1602/378 simplified gives 89/21
So, 36/54 + 75/21 = 89/21
In mixed form: 45/21

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