Add 72/6 and 90/21, Solve 12 0/6 + 4 6/21 as a fraction

Add 72/6 and 90/21

1^st number: 12 0/6, 2^nd number: 4 6/21

72/6 + 90/21 is 114/7.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 6 × 7 = 42,
72/6 = 72 × 7/6 × 7 = 504/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42
Add the two like fractions:
504/42 + 180/42 = 504 + 180/42 = 684/42
684/42 simplified gives 114/7
So, 72/6 + 90/21 = 114/7
In mixed form: 162/7

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