Add 21/35 and 80/90
21/35 + 80/90 is 67/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 35 × 18 = 630,
21/35 = 21 × 18/35 × 18 = 378/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
80/90 = 80 × 7/90 × 7 = 560/630 - Add the two like fractions:
378/630 + 560/630 = 378 + 560/630 = 938/630 - 938/630 simplified gives 67/45
- So, 21/35 + 80/90 = 67/45
In mixed form: 122/45
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