Add 84/80 and 36/21, Solve 1 4/80 + 1 15/21 as a fraction

Add 84/80 and 36/21

1^st number: 1 4/80, 2^nd number: 1 15/21

84/80 + 36/21 is 387/140.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
84/80 = 84 × 21/80 × 21 = 1764/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
36/21 = 36 × 80/21 × 80 = 2880/1680
Add the two like fractions:
1764/1680 + 2880/1680 = 1764 + 2880/1680 = 4644/1680
4644/1680 simplified gives 387/140
So, 84/80 + 36/21 = 387/140
In mixed form: 2107/140

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