Add 12/21 and 3/45
12/21 + 3/45 is 67/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
12/21 = 12 × 15/21 × 15 = 180/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
3/45 = 3 × 7/45 × 7 = 21/315 - Add the two like fractions:
180/315 + 21/315 = 180 + 21/315 = 201/315 - 201/315 simplified gives 67/105
- So, 12/21 + 3/45 = 67/105
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