Add 7/21 and 80/90
7/21 + 80/90 is 11/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
7/21 = 7 × 30/21 × 30 = 210/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
80/90 = 80 × 7/90 × 7 = 560/630 - Add the two like fractions:
210/630 + 560/630 = 210 + 560/630 = 770/630 - 770/630 simplified gives 11/9
- So, 7/21 + 80/90 = 11/9
In mixed form: 12/9
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