Add 72/21 and 10/80, Solve 3 9/21 + 10/80 as a fraction

Add 72/21 and 10/80

1^st number: 3 9/21, 2^nd number: 10/80

72/21 + 10/80 is 199/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
72/21 = 72 × 80/21 × 80 = 5760/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
10/80 = 10 × 21/80 × 21 = 210/1680
Add the two like fractions:
5760/1680 + 210/1680 = 5760 + 210/1680 = 5970/1680
5970/1680 simplified gives 199/56
So, 72/21 + 10/80 = 199/56
In mixed form: 331/56

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