Add 18/20 and 30/21, Solve 18/20 + 1 9/21 as a fraction

Add 18/20 and 30/21

1^st number: 18/20, 2^nd number: 1 9/21

18/20 + 30/21 is 163/70.

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,
18/20 = 18 × 21/20 × 21 = 378/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
30/21 = 30 × 20/21 × 20 = 600/420
Add the two like fractions:
378/420 + 600/420 = 378 + 600/420 = 978/420
978/420 simplified gives 163/70
So, 18/20 + 30/21 = 163/70
In mixed form: 223/70

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