Add 90/80 and 21/45, Solve 1 10/80 + 21/45 as a fraction

Add 90/80 and 21/45

1^st number: 1 10/80, 2^nd number: 21/45

90/80 + 21/45 is 191/120.

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,
21/45 = 21 × 16/45 × 16 = 336/720
Add the two like fractions:
810/720 + 336/720 = 810 + 336/720 = 1146/720
1146/720 simplified gives 191/120
So, 90/80 + 21/45 = 191/120
In mixed form: 171/120

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