Add 30/21 and 12/72, Solve 1 9/21 + 12/72 as a fraction

Add 30/21 and 12/72

1^st number: 1 9/21, 2^nd number: 12/72

30/21 + 12/72 is 67/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
30/21 = 30 × 24/21 × 24 = 720/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504
Add the two like fractions:
720/504 + 84/504 = 720 + 84/504 = 804/504
804/504 simplified gives 67/42
So, 30/21 + 12/72 = 67/42
In mixed form: 125/42

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