Add 5/21 and 90/80, Solve 5/21 + 1 10/80 as a fraction

Add 5/21 and 90/80

1^st number: 5/21, 2^nd number: 1 10/80

5/21 + 90/80 is 229/168.

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,
5/21 = 5 × 80/21 × 80 = 400/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680
Add the two like fractions:
400/1680 + 1890/1680 = 400 + 1890/1680 = 2290/1680
2290/1680 simplified gives 229/168
So, 5/21 + 90/80 = 229/168
In mixed form: 161/168

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