Add 20/45 and 15/21
20/45 + 15/21 is 73/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
15/21 = 15 × 15/21 × 15 = 225/315 - Add the two like fractions:
140/315 + 225/315 = 140 + 225/315 = 365/315 - 365/315 simplified gives 73/63
- So, 20/45 + 15/21 = 73/63
In mixed form: 110/63
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