Add 10/42 and 40/12, Solve 10/42 + 3 4/12 as a fraction

Add 10/42 and 40/12

1^st number: 10/42, 2^nd number: 3 4/12

10/42 + 40/12 is 25/7.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
10/42 = 10 × 2/42 × 2 = 20/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84
Add the two like fractions:
20/84 + 280/84 = 20 + 280/84 = 300/84
300/84 simplified gives 25/7
So, 10/42 + 40/12 = 25/7
In mixed form: 34/7

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