Add 42/80 and 70/9, Solve 42/80 + 7 7/9 as a fraction

Add 42/80 and 70/9

1^st number: 42/80, 2^nd number: 7 7/9

42/80 + 70/9 is 2989/360.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720
Likewise, for the 2nd fraction, since 9 × 80 = 720,
70/9 = 70 × 80/9 × 80 = 5600/720
Add the two like fractions:
378/720 + 5600/720 = 378 + 5600/720 = 5978/720
5978/720 simplified gives 2989/360
So, 42/80 + 70/9 = 2989/360
In mixed form: 8109/360

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