Add 81/30 and 4/7, Solve 2 21/30 + 4/7 as a fraction

Add 81/30 and 4/7

1^st number: 2 21/30, 2^nd number: 4/7

81/30 + 4/7 is 229/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 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 7 × 30 = 210,
4/7 = 4 × 30/7 × 30 = 120/210
Add the two like fractions:
567/210 + 120/210 = 567 + 120/210 = 687/210
687/210 simplified gives 229/70
So, 81/30 + 4/7 = 229/70
In mixed form: 319/70

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