Add 90/80 and 21/90
1st number: 1 10/80, 2nd number: 21/90
90/80 + 21/90 is 163/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 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 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Add the two like fractions:
810/720 + 168/720 = 810 + 168/720 = 978/720 - 978/720 simplified gives 163/120
- So, 90/80 + 21/90 = 163/120
In mixed form: 143/120
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