Add 90/72 and 81/80, Solve 1 18/72 + 1 1/80 as a fraction

Add 90/72 and 81/80

1^st number: 1 18/72, 2^nd number: 1 1/80

90/72 + 81/80 is 181/80.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 80 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 72 × 10 = 720,
90/72 = 90 × 10/72 × 10 = 900/720
Likewise, for the 2nd fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720
Add the two like fractions:
900/720 + 729/720 = 900 + 729/720 = 1629/720
1629/720 simplified gives 181/80
So, 90/72 + 81/80 = 181/80
In mixed form: 221/80

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