Add 9/12 and 45/80, Solve 9/12 + 45/80 as a fraction

Add 9/12 and 45/80

9/12 + 45/80 is 21/16.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 12 × 20 = 240,
9/12 = 9 × 20/12 × 20 = 180/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
45/80 = 45 × 3/80 × 3 = 135/240
Add the two like fractions:
180/240 + 135/240 = 180 + 135/240 = 315/240
315/240 simplified gives 21/16
So, 9/12 + 45/80 = 21/16
In mixed form: 15/16

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