Add 10/12 and 9/42, Solve 10/12 + 9/42 as a fraction

Add 10/12 and 9/42

10/12 + 9/42 is 22/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
10/12 = 10 × 7/12 × 7 = 70/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
9/42 = 9 × 2/42 × 2 = 18/84
Add the two like fractions:
70/84 + 18/84 = 70 + 18/84 = 88/84
88/84 simplified gives 22/21
So, 10/12 + 9/42 = 22/21
In mixed form: 11/21

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