Add 7/2 and 30/21, Solve 3 1/2 + 1 9/21 as a fraction

Add 7/2 and 30/21

1^st number: 3 1/2, 2^nd number: 1 9/21

7/2 + 30/21 is 69/14.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 2 × 21 = 42,
7/2 = 7 × 21/2 × 21 = 147/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
30/21 = 30 × 2/21 × 2 = 60/42
Add the two like fractions:
147/42 + 60/42 = 147 + 60/42 = 207/42
207/42 simplified gives 69/14
So, 7/2 + 30/21 = 69/14
In mixed form: 413/14

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