Add 21/80 and 75/28, Solve 21/80 + 2 19/28 as a fraction

Add 21/80 and 75/28

1^st number: 21/80, 2^nd number: 2 19/28

21/80 + 75/28 is 1647/560.

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,
21/80 = 21 × 7/80 × 7 = 147/560
Likewise, for the 2nd fraction, since 28 × 20 = 560,
75/28 = 75 × 20/28 × 20 = 1500/560
Add the two like fractions:
147/560 + 1500/560 = 147 + 1500/560 = 1647/560
So, 21/80 + 75/28 = 1647/560
In mixed form: 2527/560

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