Add 90/21 and 10/80, Solve 4 6/21 + 10/80 as a fraction

Add 90/21 and 10/80

1^st number: 4 6/21, 2^nd number: 10/80

90/21 + 10/80 is 247/56.

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,
90/21 = 90 × 80/21 × 80 = 7200/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
10/80 = 10 × 21/80 × 21 = 210/1680
Add the two like fractions:
7200/1680 + 210/1680 = 7200 + 210/1680 = 7410/1680
7410/1680 simplified gives 247/56
So, 90/21 + 10/80 = 247/56
In mixed form: 423/56

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