Add 28/21 and 3/80, Solve 1 7/21 + 3/80 as a fraction

Add 28/21 and 3/80

1^st number: 1 7/21, 2^nd number: 3/80

28/21 + 3/80 is 329/240.

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,
28/21 = 28 × 80/21 × 80 = 2240/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
3/80 = 3 × 21/80 × 21 = 63/1680
Add the two like fractions:
2240/1680 + 63/1680 = 2240 + 63/1680 = 2303/1680
2303/1680 simplified gives 329/240
So, 28/21 + 3/80 = 329/240
In mixed form: 189/240

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