Add 3/2 and 81/21, Solve 1 1/2 + 3 18/21 as a fraction

Add 3/2 and 81/21

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

3/2 + 81/21 is 75/14.

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,
3/2 = 3 × 21/2 × 21 = 63/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42
Add the two like fractions:
63/42 + 162/42 = 63 + 162/42 = 225/42
225/42 simplified gives 75/14
So, 3/2 + 81/21 = 75/14
In mixed form: 55/14

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