Add 20/45 and 63/21
1st number: 20/45, 2nd number: 3 0/21
20/45 + 63/21 is 31/9.
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,
63/21 = 63 × 15/21 × 15 = 945/315 - Add the two like fractions:
140/315 + 945/315 = 140 + 945/315 = 1085/315 - 1085/315 simplified gives 31/9
- So, 20/45 + 63/21 = 31/9
In mixed form: 34/9
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