Add 81/20 and 3/42, Solve 4 1/20 + 3/42 as a fraction

Add 81/20 and 3/42

1^st number: 4 1/20, 2^nd number: 3/42

81/20 + 3/42 is 577/140.

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,
81/20 = 81 × 21/20 × 21 = 1701/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
3/42 = 3 × 10/42 × 10 = 30/420
Add the two like fractions:
1701/420 + 30/420 = 1701 + 30/420 = 1731/420
1731/420 simplified gives 577/140
So, 81/20 + 3/42 = 577/140
In mixed form: 417/140

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