Add 81/21 and 2/45, Solve 3 18/21 + 2/45 as a fraction

Add 81/21 and 2/45

1^st number: 3 18/21, 2^nd number: 2/45

81/21 + 2/45 is 1229/315.

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,
2/45 = 2 × 7/45 × 7 = 14/315
Add the two like fractions:
1215/315 + 14/315 = 1215 + 14/315 = 1229/315
So, 81/21 + 2/45 = 1229/315
In mixed form: 3284/315

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