Add 6/4 and 15/21, Solve 1 2/4 + 15/21 as a fraction

Add 6/4 and 15/21

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

6/4 + 15/21 is 31/14.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
6/4 = 6 × 21/4 × 21 = 126/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84
Add the two like fractions:
126/84 + 60/84 = 126 + 60/84 = 186/84
186/84 simplified gives 31/14
So, 6/4 + 15/21 = 31/14
In mixed form: 23/14

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