Add 15/21 and 63/4, Solve 15/21 + 15 3/4 as a fraction

Add 15/21 and 63/4

1^st number: 15/21, 2^nd number: 15 3/4

15/21 + 63/4 is 461/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
63/4 = 63 × 21/4 × 21 = 1323/84
Add the two like fractions:
60/84 + 1323/84 = 60 + 1323/84 = 1383/84
1383/84 simplified gives 461/28
So, 15/21 + 63/4 = 461/28
In mixed form: 1613/28

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