Add 81/21 and 20/45
1st number: 3 18/21, 2nd number: 20/45
81/21 + 20/45 is 271/63.
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,
81/21 = 81 × 15/21 × 15 = 1215/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
1215/315 + 140/315 = 1215 + 140/315 = 1355/315 - 1355/315 simplified gives 271/63
- So, 81/21 + 20/45 = 271/63
In mixed form: 419/63
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