Add 27/20 and 15/21, Solve 1 7/20 + 15/21 as a fraction

Add 27/20 and 15/21

1^st number: 1 7/20, 2^nd number: 15/21

27/20 + 15/21 is 289/140.

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,
15/21 = 15 × 20/21 × 20 = 300/420
Add the two like fractions:
567/420 + 300/420 = 567 + 300/420 = 867/420
867/420 simplified gives 289/140
So, 27/20 + 15/21 = 289/140
In mixed form: 29/140

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