Add 12/21 and 36/90
12/21 + 36/90 is 34/35.
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,
36/90 = 36 × 7/90 × 7 = 252/630 - Add the two like fractions:
360/630 + 252/630 = 360 + 252/630 = 612/630 - 612/630 simplified gives 34/35
- So, 12/21 + 36/90 = 34/35
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