Add 90/12 and 80/21, Solve 7 6/12 + 3 17/21 as a fraction

Add 90/12 and 80/21

1^st number: 7 6/12, 2^nd number: 3 17/21

90/12 + 80/21 is 475/42.

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,
80/21 = 80 × 4/21 × 4 = 320/84
Add the two like fractions:
630/84 + 320/84 = 630 + 320/84 = 950/84
950/84 simplified gives 475/42
So, 90/12 + 80/21 = 475/42
In mixed form: 1113/42

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