Add 90/12 and 8/21, Solve 7 6/12 + 8/21 as a fraction

Add 90/12 and 8/21

1^st number: 7 6/12, 2^nd number: 8/21

90/12 + 8/21 is 331/42.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
8/21 = 8 × 4/21 × 4 = 32/84
Add the two like fractions:
630/84 + 32/84 = 630 + 32/84 = 662/84
662/84 simplified gives 331/42
So, 90/12 + 8/21 = 331/42
In mixed form: 737/42

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