Add 21/20 and 84/42, Solve 1 1/20 + 2 0/42 as a fraction

Add 21/20 and 84/42

1^st number: 1 1/20, 2^nd number: 2 0/42

21/20 + 84/42 is 61/20.

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,
21/20 = 21 × 21/20 × 21 = 441/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
84/42 = 84 × 10/42 × 10 = 840/420
Add the two like fractions:
441/420 + 840/420 = 441 + 840/420 = 1281/420
1281/420 simplified gives 61/20
So, 21/20 + 84/42 = 61/20
In mixed form: 31/20

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