Add 84/8 and 72/21, Solve 10 4/8 + 3 9/21 as a fraction

Add 84/8 and 72/21

1^st number: 10 4/8, 2^nd number: 3 9/21

84/8 + 72/21 is 195/14.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
84/8 = 84 × 21/8 × 21 = 1764/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168
Add the two like fractions:
1764/168 + 576/168 = 1764 + 576/168 = 2340/168
2340/168 simplified gives 195/14
So, 84/8 + 72/21 = 195/14
In mixed form: 1313/14

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