Add 21/5 and 28/63, Solve 4 1/5 + 28/63 as a fraction

Add 21/5 and 28/63

1^st number: 4 1/5, 2^nd number: 28/63

21/5 + 28/63 is 209/45.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 63 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 5 × 63 = 315,
21/5 = 21 × 63/5 × 63 = 1323/315
Likewise, for the 2nd fraction, since 63 × 5 = 315,
28/63 = 28 × 5/63 × 5 = 140/315
Add the two like fractions:
1323/315 + 140/315 = 1323 + 140/315 = 1463/315
1463/315 simplified gives 209/45
So, 21/5 + 28/63 = 209/45
In mixed form: 429/45

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