Add 81/21 and 90/25
1st number: 3 18/21, 2nd number: 3 15/25
81/21 + 90/25 is 261/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 21 × 25 = 525,
81/21 = 81 × 25/21 × 25 = 2025/525 - Likewise, for the 2nd fraction, since 25 × 21 = 525,
90/25 = 90 × 21/25 × 21 = 1890/525 - Add the two like fractions:
2025/525 + 1890/525 = 2025 + 1890/525 = 3915/525 - 3915/525 simplified gives 261/35
- So, 81/21 + 90/25 = 261/35
In mixed form: 716/35
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