Add 3/21 and 18/4, Solve 3/21 + 4 2/4 as a fraction

Add 3/21 and 18/4

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

3/21 + 18/4 is 65/14.

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,
3/21 = 3 × 4/21 × 4 = 12/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84
Add the two like fractions:
12/84 + 378/84 = 12 + 378/84 = 390/84
390/84 simplified gives 65/14
So, 3/21 + 18/4 = 65/14
In mixed form: 49/14

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