Add 21/54 and 63/16, Solve 21/54 + 3 15/16 as a fraction

Add 21/54 and 63/16

1^st number: 21/54, 2^nd number: 3 15/16

21/54 + 63/16 is 623/144.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 16 is 432

Next, find the equivalent fraction of both fractional numbers with denominator 432
For the 1st fraction, since 54 × 8 = 432,
21/54 = 21 × 8/54 × 8 = 168/432
Likewise, for the 2nd fraction, since 16 × 27 = 432,
63/16 = 63 × 27/16 × 27 = 1701/432
Add the two like fractions:
168/432 + 1701/432 = 168 + 1701/432 = 1869/432
1869/432 simplified gives 623/144
So, 21/54 + 63/16 = 623/144
In mixed form: 447/144

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