Add 90/21 and 18/80, Solve 4 6/21 + 18/80 as a fraction

Add 90/21 and 18/80

1^st number: 4 6/21, 2^nd number: 18/80

90/21 + 18/80 is 1263/280.

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,
18/80 = 18 × 21/80 × 21 = 378/1680
Add the two like fractions:
7200/1680 + 378/1680 = 7200 + 378/1680 = 7578/1680
7578/1680 simplified gives 1263/280
So, 90/21 + 18/80 = 1263/280
In mixed form: 4143/280

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