Add 27/20 and 84/21, Solve 1 7/20 + 4 0/21 as a fraction

Add 27/20 and 84/21

1^st number: 1 7/20, 2^nd number: 4 0/21

27/20 + 84/21 is 107/20.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
84/21 = 84 × 20/21 × 20 = 1680/420
Add the two like fractions:
567/420 + 1680/420 = 567 + 1680/420 = 2247/420
2247/420 simplified gives 107/20
So, 27/20 + 84/21 = 107/20
In mixed form: 57/20

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