Add 81/90 and 4/21
81/90 + 4/21 is 229/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
4/21 = 4 × 30/21 × 30 = 120/630 - Add the two like fractions:
567/630 + 120/630 = 567 + 120/630 = 687/630 - 687/630 simplified gives 229/210
- So, 81/90 + 4/21 = 229/210
In mixed form: 119/210
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