Add 21/80 and 16/9, Solve 21/80 + 1 7/9 as a fraction

Add 21/80 and 16/9

1^st number: 21/80, 2^nd number: 1 7/9

21/80 + 16/9 is 1469/720.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720
Likewise, for the 2nd fraction, since 9 × 80 = 720,
16/9 = 16 × 80/9 × 80 = 1280/720
Add the two like fractions:
189/720 + 1280/720 = 189 + 1280/720 = 1469/720
So, 21/80 + 16/9 = 1469/720
In mixed form: 229/720

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