Add 81/42 and 32/20, Solve 1 39/42 + 1 12/20 as a fraction

Add 81/42 and 32/20

1^st number: 1 39/42, 2^nd number: 1 12/20

81/42 + 32/20 is 247/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
81/42 = 81 × 10/42 × 10 = 810/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
32/20 = 32 × 21/20 × 21 = 672/420
Add the two like fractions:
810/420 + 672/420 = 810 + 672/420 = 1482/420
1482/420 simplified gives 247/70
So, 81/42 + 32/20 = 247/70
In mixed form: 337/70

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