Add 21/42 and 27/20, Solve 21/42 + 1 7/20 as a fraction

Add 21/42 and 27/20

1^st number: 21/42, 2^nd number: 1 7/20

21/42 + 27/20 is 37/20.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420
Add the two like fractions:
210/420 + 567/420 = 210 + 567/420 = 777/420
777/420 simplified gives 37/20
So, 21/42 + 27/20 = 37/20
In mixed form: 117/20

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