Add 84/90 and 15/21
84/90 + 15/21 is 173/105.
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,
84/90 = 84 × 7/90 × 7 = 588/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
15/21 = 15 × 30/21 × 30 = 450/630 - Add the two like fractions:
588/630 + 450/630 = 588 + 450/630 = 1038/630 - 1038/630 simplified gives 173/105
- So, 84/90 + 15/21 = 173/105
In mixed form: 168/105
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