Add 70/42 and 9/80, Solve 1 28/42 + 9/80 as a fraction

Add 70/42 and 9/80

1^st number: 1 28/42, 2^nd number: 9/80

70/42 + 9/80 is 427/240.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
9/80 = 9 × 21/80 × 21 = 189/1680
Add the two like fractions:
2800/1680 + 189/1680 = 2800 + 189/1680 = 2989/1680
2989/1680 simplified gives 427/240
So, 70/42 + 9/80 = 427/240
In mixed form: 1187/240

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