Add 5/21 and 81/90
5/21 + 81/90 is 239/210.
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,
5/21 = 5 × 30/21 × 30 = 150/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
150/630 + 567/630 = 150 + 567/630 = 717/630 - 717/630 simplified gives 239/210
- So, 5/21 + 81/90 = 239/210
In mixed form: 129/210
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