Add 40/12 and 63/42, Solve 3 4/12 + 1 21/42 as a fraction

Add 40/12 and 63/42

1^st number: 3 4/12, 2^nd number: 1 21/42

40/12 + 63/42 is 29/6.

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,
40/12 = 40 × 7/12 × 7 = 280/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
63/42 = 63 × 2/42 × 2 = 126/84
Add the two like fractions:
280/84 + 126/84 = 280 + 126/84 = 406/84
406/84 simplified gives 29/6
So, 40/12 + 63/42 = 29/6
In mixed form: 45/6

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