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

Add 90/21 and 4/80

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

90/21 + 4/80 is 607/140.

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,
4/80 = 4 × 21/80 × 21 = 84/1680
Add the two like fractions:
7200/1680 + 84/1680 = 7200 + 84/1680 = 7284/1680
7284/1680 simplified gives 607/140
So, 90/21 + 4/80 = 607/140
In mixed form: 447/140

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