Add 21/90 and 90/80
1st number: 21/90, 2nd number: 1 10/80
21/90 + 90/80 is 163/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
90/80 = 90 × 9/80 × 9 = 810/720 - Add the two like fractions:
168/720 + 810/720 = 168 + 810/720 = 978/720 - 978/720 simplified gives 163/120
- So, 21/90 + 90/80 = 163/120
In mixed form: 143/120
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