Add 81/28 and 21/30, Solve 2 25/28 + 21/30 as a fraction

Add 81/28 and 21/30

1^st number: 2 25/28, 2^nd number: 21/30

81/28 + 21/30 is 503/140.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 28 × 15 = 420,
81/28 = 81 × 15/28 × 15 = 1215/420
Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420
Add the two like fractions:
1215/420 + 294/420 = 1215 + 294/420 = 1509/420
1509/420 simplified gives 503/140
So, 81/28 + 21/30 = 503/140
In mixed form: 383/140

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