Add 4/21 and 12/90
4/21 + 12/90 is 34/105.
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,
4/21 = 4 × 30/21 × 30 = 120/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630 - Add the two like fractions:
120/630 + 84/630 = 120 + 84/630 = 204/630 - 204/630 simplified gives 34/105
- So, 4/21 + 12/90 = 34/105
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