Add 12/90 and 18/21
12/90 + 18/21 is 104/105.
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,
12/90 = 12 × 7/90 × 7 = 84/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
18/21 = 18 × 30/21 × 30 = 540/630 - Add the two like fractions:
84/630 + 540/630 = 84 + 540/630 = 624/630 - 624/630 simplified gives 104/105
- So, 12/90 + 18/21 = 104/105
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