Add 90/80 and 40/45, Solve 1 10/80 + 40/45 as a fraction

Add 90/80 and 40/45

1^st number: 1 10/80, 2^nd number: 40/45

90/80 + 40/45 is 145/72.

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,
90/80 = 90 × 9/80 × 9 = 810/720
Likewise, for the 2nd fraction, since 45 × 16 = 720,
40/45 = 40 × 16/45 × 16 = 640/720
Add the two like fractions:
810/720 + 640/720 = 810 + 640/720 = 1450/720
1450/720 simplified gives 145/72
So, 90/80 + 40/45 = 145/72
In mixed form: 21/72

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