Add 12/21 and 84/90
12/21 + 84/90 is 158/105.
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,
12/21 = 12 × 30/21 × 30 = 360/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
84/90 = 84 × 7/90 × 7 = 588/630 - Add the two like fractions:
360/630 + 588/630 = 360 + 588/630 = 948/630 - 948/630 simplified gives 158/105
- So, 12/21 + 84/90 = 158/105
In mixed form: 153/105
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