Add 42/21 and 21/80, Solve 2 0/21 + 21/80 as a fraction

Add 42/21 and 21/80

1^st number: 2 0/21, 2^nd number: 21/80

42/21 + 21/80 is 181/80.

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,
42/21 = 42 × 80/21 × 80 = 3360/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
21/80 = 21 × 21/80 × 21 = 441/1680
Add the two like fractions:
3360/1680 + 441/1680 = 3360 + 441/1680 = 3801/1680
3801/1680 simplified gives 181/80
So, 42/21 + 21/80 = 181/80
In mixed form: 221/80

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