Add 20/45 and 63/42, Solve 20/45 + 1 21/42 as a fraction

Add 20/45 and 63/42

1^st number: 20/45, 2^nd number: 1 21/42

20/45 + 63/42 is 35/18.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
63/42 = 63 × 15/42 × 15 = 945/630
Add the two like fractions:
280/630 + 945/630 = 280 + 945/630 = 1225/630
1225/630 simplified gives 35/18
So, 20/45 + 63/42 = 35/18
In mixed form: 117/18

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