Add 27/20 and 5/21, Solve 1 7/20 + 5/21 as a fraction

Add 27/20 and 5/21

1^st number: 1 7/20, 2^nd number: 5/21

27/20 + 5/21 is 667/420.

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,
5/21 = 5 × 20/21 × 20 = 100/420
Add the two like fractions:
567/420 + 100/420 = 567 + 100/420 = 667/420
So, 27/20 + 5/21 = 667/420
In mixed form: 1247/420

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