Add 7/21 and 81/80, Solve 7/21 + 1 1/80 as a fraction

Add 7/21 and 81/80

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

7/21 + 81/80 is 323/240.

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,
7/21 = 7 × 80/21 × 80 = 560/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680
Add the two like fractions:
560/1680 + 1701/1680 = 560 + 1701/1680 = 2261/1680
2261/1680 simplified gives 323/240
So, 7/21 + 81/80 = 323/240
In mixed form: 183/240

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