Add 21/63 and 20/45
21/63 + 20/45 is 7/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
105/315 + 140/315 = 105 + 140/315 = 245/315 - 245/315 simplified gives 7/9
- So, 21/63 + 20/45 = 7/9
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