Add 27/21 and 20/80, Solve 1 6/21 + 20/80 as a fraction

Add 27/21 and 20/80

1^st number: 1 6/21, 2^nd number: 20/80

27/21 + 20/80 is 43/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
27/21 = 27 × 80/21 × 80 = 2160/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680
Add the two like fractions:
2160/1680 + 420/1680 = 2160 + 420/1680 = 2580/1680
2580/1680 simplified gives 43/28
So, 27/21 + 20/80 = 43/28
In mixed form: 115/28

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