Add 84/80 and 75/42, Solve 1 4/80 + 1 33/42 as a fraction

Add 84/80 and 75/42

1^st number: 1 4/80, 2^nd number: 1 33/42

84/80 + 75/42 is 397/140.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 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 42 × 40 = 1680,
75/42 = 75 × 40/42 × 40 = 3000/1680
Add the two like fractions:
1764/1680 + 3000/1680 = 1764 + 3000/1680 = 4764/1680
4764/1680 simplified gives 397/140
So, 84/80 + 75/42 = 397/140
In mixed form: 2117/140

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