Add 80/90 and 21/80, Solve 80/90 + 21/80 as a fraction

Add 80/90 and 21/80

80/90 + 21/80 is 829/720.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 90 × 8 = 720,
80/90 = 80 × 8/90 × 8 = 640/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720
Add the two like fractions:
640/720 + 189/720 = 640 + 189/720 = 829/720
So, 80/90 + 21/80 = 829/720
In mixed form: 1109/720

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