Add 3/80 and 81/28, Solve 3/80 + 2 25/28 as a fraction

Add 3/80 and 81/28

1^st number: 3/80, 2^nd number: 2 25/28

3/80 + 81/28 is 1641/560.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
3/80 = 3 × 7/80 × 7 = 21/560
Likewise, for the 2nd fraction, since 28 × 20 = 560,
81/28 = 81 × 20/28 × 20 = 1620/560
Add the two like fractions:
21/560 + 1620/560 = 21 + 1620/560 = 1641/560
So, 3/80 + 81/28 = 1641/560
In mixed form: 2521/560

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