Add 80/28 and 9/21, Solve 2 24/28 + 9/21 as a fraction

Add 80/28 and 9/21

1^st number: 2 24/28, 2^nd number: 9/21

80/28 + 9/21 is 23/7.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
80/28 = 80 × 3/28 × 3 = 240/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84
Add the two like fractions:
240/84 + 36/84 = 240 + 36/84 = 276/84
276/84 simplified gives 23/7
So, 80/28 + 9/21 = 23/7
In mixed form: 32/7

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