Add 81/80 and 70/45, Solve 1 1/80 + 1 25/45 as a fraction

Add 81/80 and 70/45

1^st number: 1 1/80, 2^nd number: 1 25/45

81/80 + 70/45 is 1849/720.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720

Next, find the equivalent fraction of both fractional numbers with denominator 720
For the 1st fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720
Likewise, for the 2nd fraction, since 45 × 16 = 720,
70/45 = 70 × 16/45 × 16 = 1120/720
Add the two like fractions:
729/720 + 1120/720 = 729 + 1120/720 = 1849/720
So, 81/80 + 70/45 = 1849/720
In mixed form: 2409/720

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