Add 12/21 and 20/45
12/21 + 20/45 is 64/63.
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,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
180/315 + 140/315 = 180 + 140/315 = 320/315 - 320/315 simplified gives 64/63
- So, 12/21 + 20/45 = 64/63
In mixed form: 11/63
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