Add 63/42 and 9/20, Solve 1 21/42 + 9/20 as a fraction

Add 63/42 and 9/20

1^st number: 1 21/42, 2^nd number: 9/20

63/42 + 9/20 is 39/20.

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,
63/42 = 63 × 10/42 × 10 = 630/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
9/20 = 9 × 21/20 × 21 = 189/420
Add the two like fractions:
630/420 + 189/420 = 630 + 189/420 = 819/420
819/420 simplified gives 39/20
So, 63/42 + 9/20 = 39/20
In mixed form: 119/20

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