Add 12/21 and 35/45
12/21 + 35/45 is 85/63.
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,
35/45 = 35 × 7/45 × 7 = 245/315 - Add the two like fractions:
180/315 + 245/315 = 180 + 245/315 = 425/315 - 425/315 simplified gives 85/63
- So, 12/21 + 35/45 = 85/63
In mixed form: 122/63
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