Add 9/80 and 21/18, Solve 9/80 + 1 3/18 as a fraction

Add 9/80 and 21/18

1^st number: 9/80, 2^nd number: 1 3/18

9/80 + 21/18 is 307/240.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
9/80 = 9 × 9/80 × 9 = 81/720
Likewise, for the 2nd fraction, since 18 × 40 = 720,
21/18 = 21 × 40/18 × 40 = 840/720
Add the two like fractions:
81/720 + 840/720 = 81 + 840/720 = 921/720
921/720 simplified gives 307/240
So, 9/80 + 21/18 = 307/240
In mixed form: 167/240

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