Add 81/21 and 70/45
1st number: 3 18/21, 2nd number: 1 25/45
81/21 + 70/45 is 341/63.
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,
70/45 = 70 × 7/45 × 7 = 490/315 - Add the two like fractions:
1215/315 + 490/315 = 1215 + 490/315 = 1705/315 - 1705/315 simplified gives 341/63
- So, 81/21 + 70/45 = 341/63
In mixed form: 526/63
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