Add 81/30 and 4/21, Solve 2 21/30 + 4/21 as a fraction

Add 81/30 and 4/21

1^st number: 2 21/30, 2^nd number: 4/21

81/30 + 4/21 is 607/210.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
4/21 = 4 × 10/21 × 10 = 40/210
Add the two like fractions:
567/210 + 40/210 = 567 + 40/210 = 607/210
So, 81/30 + 4/21 = 607/210
In mixed form: 2187/210

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