Add 81/21 and 8/25, Solve 3 18/21 + 8/25 as a fraction

Add 81/21 and 8/25

1^st number: 3 18/21, 2^nd number: 8/25

81/21 + 8/25 is 731/175.

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,
8/25 = 8 × 21/25 × 21 = 168/525
Add the two like fractions:
2025/525 + 168/525 = 2025 + 168/525 = 2193/525
2193/525 simplified gives 731/175
So, 81/21 + 8/25 = 731/175
In mixed form: 431/175

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