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

Add 21/20 and 21/27

1^st number: 1 1/20, 2^nd number: 21/27

21/20 + 21/27 is 329/180.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 27 is 540

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540
Likewise, for the 2nd fraction, since 27 × 20 = 540,
21/27 = 21 × 20/27 × 20 = 420/540
Add the two like fractions:
567/540 + 420/540 = 567 + 420/540 = 987/540
987/540 simplified gives 329/180
So, 21/20 + 21/27 = 329/180
In mixed form: 1149/180

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