Add 6/18 and 75/21, Solve 6/18 + 3 12/21 as a fraction

Add 6/18 and 75/21

1^st number: 6/18, 2^nd number: 3 12/21

6/18 + 75/21 is 82/21.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
6/18 = 6 × 7/18 × 7 = 42/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
75/21 = 75 × 6/21 × 6 = 450/126
Add the two like fractions:
42/126 + 450/126 = 42 + 450/126 = 492/126
492/126 simplified gives 82/21
So, 6/18 + 75/21 = 82/21
In mixed form: 319/21

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