Add 21/16 and 20/63, Solve 1 5/16 + 20/63 as a fraction

Add 21/16 and 20/63

1^st number: 1 5/16, 2^nd number: 20/63

21/16 + 20/63 is 1643/1008.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 63 is 1008

Next, find the equivalent fraction of both fractional numbers with denominator 1008
For the 1st fraction, since 16 × 63 = 1008,
21/16 = 21 × 63/16 × 63 = 1323/1008
Likewise, for the 2nd fraction, since 63 × 16 = 1008,
20/63 = 20 × 16/63 × 16 = 320/1008
Add the two like fractions:
1323/1008 + 320/1008 = 1323 + 320/1008 = 1643/1008
So, 21/16 + 20/63 = 1643/1008
In mixed form: 1635/1008

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