Add 72/42 and 90/54, Solve 1 30/42 + 1 36/54 as a fraction

Add 72/42 and 90/54

1^st number: 1 30/42, 2^nd number: 1 36/54

72/42 + 90/54 is 71/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
72/42 = 72 × 9/42 × 9 = 648/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
90/54 = 90 × 7/54 × 7 = 630/378
Add the two like fractions:
648/378 + 630/378 = 648 + 630/378 = 1278/378
1278/378 simplified gives 71/21
So, 72/42 + 90/54 = 71/21
In mixed form: 38/21

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