Add 18/21 and 25/4, Solve 18/21 + 6 1/4 as a fraction

Add 18/21 and 25/4

1^st number: 18/21, 2^nd number: 6 1/4

18/21 + 25/4 is 199/28.

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,
18/21 = 18 × 4/21 × 4 = 72/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
25/4 = 25 × 21/4 × 21 = 525/84
Add the two like fractions:
72/84 + 525/84 = 72 + 525/84 = 597/84
597/84 simplified gives 199/28
So, 18/21 + 25/4 = 199/28
In mixed form: 73/28

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