Add 75/80 and 70/42, Solve 75/80 + 1 28/42 as a fraction

Add 75/80 and 70/42

1^st number: 75/80, 2^nd number: 1 28/42

75/80 + 70/42 is 125/48.

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,
75/80 = 75 × 21/80 × 21 = 1575/1680
Likewise, for the 2nd fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680
Add the two like fractions:
1575/1680 + 2800/1680 = 1575 + 2800/1680 = 4375/1680
4375/1680 simplified gives 125/48
So, 75/80 + 70/42 = 125/48
In mixed form: 229/48

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