Add 21/20 and 18/84, Solve 1 1/20 + 18/84 as a fraction

Add 21/20 and 18/84

1^st number: 1 1/20, 2^nd number: 18/84

21/20 + 18/84 is 177/140.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 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 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Add the two like fractions:
441/420 + 90/420 = 441 + 90/420 = 531/420
531/420 simplified gives 177/140
So, 21/20 + 18/84 = 177/140
In mixed form: 137/140

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