Add 21/35 and 84/90
21/35 + 84/90 is 23/15.
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,
84/90 = 84 × 7/90 × 7 = 588/630 - Add the two like fractions:
378/630 + 588/630 = 378 + 588/630 = 966/630 - 966/630 simplified gives 23/15
- So, 21/35 + 84/90 = 23/15
In mixed form: 18/15
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