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

Add 9/21 and 4/80

9/21 + 4/80 is 67/140.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 21 × 80 = 1680,
9/21 = 9 × 80/21 × 80 = 720/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
4/80 = 4 × 21/80 × 21 = 84/1680
Add the two like fractions:
720/1680 + 84/1680 = 720 + 84/1680 = 804/1680
804/1680 simplified gives 67/140
So, 9/21 + 4/80 = 67/140

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