Add 40/9 and 21/80, Solve 4 4/9 + 21/80 as a fraction

Add 40/9 and 21/80

1^st number: 4 4/9, 2^nd number: 21/80

40/9 + 21/80 is 3389/720.

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

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 9 × 80 = 720,
40/9 = 40 × 80/9 × 80 = 3200/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720
Add the two like fractions:
3200/720 + 189/720 = 3200 + 189/720 = 3389/720
So, 40/9 + 21/80 = 3389/720
In mixed form: 4509/720

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