Add 15/21 and 35/80, Solve 15/21 + 35/80 as a fraction

Add 15/21 and 35/80

15/21 + 35/80 is 129/112.

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,
15/21 = 15 × 80/21 × 80 = 1200/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
35/80 = 35 × 21/80 × 21 = 735/1680
Add the two like fractions:
1200/1680 + 735/1680 = 1200 + 735/1680 = 1935/1680
1935/1680 simplified gives 129/112
So, 15/21 + 35/80 = 129/112
In mixed form: 117/112

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