Add 12/20 and 72/42, Solve 12/20 + 1 30/42 as a fraction

Add 12/20 and 72/42

1^st number: 12/20, 2^nd number: 1 30/42

12/20 + 72/42 is 81/35.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
12/20 = 12 × 21/20 × 21 = 252/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
72/42 = 72 × 10/42 × 10 = 720/420
Add the two like fractions:
252/420 + 720/420 = 252 + 720/420 = 972/420
972/420 simplified gives 81/35
So, 12/20 + 72/42 = 81/35
In mixed form: 211/35

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